Heterocyclic compound and organic light-emitting device including the same

ABSTRACT

A heterocyclic compound and an organic light-emitting device including the same are provided. The heterocyclic compound may be represented by Formula 1. The substituents and variables of Formula 1 may be as defined in the present disclosure. The organic light-emitting device including the heterocyclic compound represented by Formula 1 may have a low driving voltage, high current density, and high efficiency.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean PatentApplication No. 10-2017-0021727, filed on Feb. 17, 2017, in the KoreanIntellectual Property Office, the entire content of which isincorporated herein by reference.

BACKGROUND 1. Field

One or more embodiments relate to a heterocyclic compound and an organiclight-emitting device including the same.

2. Description of the Related Art

Organic light-emitting devices are self-emission devices that producefull-color images, and also have wide viewing angles, high contrastratios, short response times, and excellent characteristics in terms ofbrightness, driving voltage, and response speed, as compared to otherdevices in the art.

An example of such organic light-emitting devices may include a firstelectrode disposed on a substrate, and a hole transport region, anemission layer, an electron transport region, and a second electrode,which are sequentially disposed on the first electrode. Holes providedfrom the first electrode may move toward the emission layer through thehole transport region, and electrons provided from the second electrodemay move toward the emission layer through the electron transportregion. Carriers, such as holes and electrons, recombine in the emissionlayer to produce excitons. These excitons transit from an excited stateto a ground state, thereby generating light.

SUMMARY

One or more embodiments include a heterocyclic compound and an organiclight-emitting device including the same.

Additional aspects will be set forth in part in the description whichfollows and, in part, will be apparent from the description, or may belearned by practice of the presented embodiments.

According to one or more embodiments, a heterocyclic compound isrepresented by Formula 1:

In Formula 1,

L₁ and L₂ may each independently be a substituted or unsubstitutedC₅-C₆₀ carbocyclic group or a substituted or unsubstituted C₁-C₆₀heterocyclic group,

R₁ and R₃ to R₁₀ may each independently be selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, —Si(Q₃₁)(Q₃₂)(Q₃₃), P(═O)(Q₃₁)(Q₃₂), a substituted orunsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀alkenyl group, a substituted or unsubstituted C₂-C₆₀ alkynyl group, asubstituted or unsubstituted C₁-C₆₀ alkoxy group, a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,a biphenyl group, and a terphenyl group,

R₂ may be (i) a C₆-C₆₀ aryl group substituted with at least one electronwithdrawing group or (ii) a substituted or unsubstituted πelectron-depleted nitrogen-containing ring group,

a1 may be an integer from 0 to 5,

a2 may be an integer from 0 to 5,

b1 may be an integer from 0 to 5,

b2 may be an integer from 1 to 5,

at least one substituent of the substituted C₅-C₆₀ carbocyclic group,the substituted C₁-C₆₀ heterocyclic group, the substituted C₁-C₆₀ alkylgroup, the substituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀alkynyl group, the substituted C₁-C₆₀ alkoxy group, the substitutedC₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀ heterocycloalkyl group,the substituted C₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀heterocycloalkenyl group, the substituted C₆-C₆₀ aryl group, thesubstituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀ arylthio group,the substituted C₁-C₆₀ heteroaryl group, the substituted monovalentnon-aromatic condensed polycyclic group, the substituted monovalentnon-aromatic condensed heteropolycyclic group, and the substituted πelectron-depleted nitrogen-containing ring group may be selected from:

deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and aC₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amidino group, a hydrazino group, a hydrazono group, aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group, a biphenylgroup, and a terphenyl group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group, a biphenylgroup, and a terphenyl group, each substituted with at least oneselected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynylgroup, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, a biphenyl group, and a terphenylgroup; and

—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ may each independently be selected from hydrogen, deuterium,—F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, anamidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkylgroup, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxygroup, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, aC₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₆-C₆₀ aryl group substituted with a C₁-C₆₀ alkyl group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup, a monovalent non-aromatic condensed heteropolycyclic group, abiphenyl group, and a terphenyl group.

According to one or more embodiments, an organic light-emitting deviceincludes: a first electrode; a second electrode facing the firstelectrode; and an organic layer between the first electrode and thesecond electrode, the organic layer including an emission layer and atleast one of the heterocyclic compound described above.

BRIEF DESCRIPTION OF THE DRAWING

These and/or other aspects will become apparent and more readilyappreciated from the following description of the embodiments, taken inconjunction with the accompanying drawing which is a schematic view ofan organic light-emitting device according to an embodiment.

DETAILED DESCRIPTION

Reference will now be made in more detail to embodiments, examples ofwhich are illustrated in the accompanying drawing. In this regard, thepresent embodiments may have different forms and should not be construedas being limited to the descriptions set forth herein. Accordingly, theembodiments are merely described below, by referring to the drawing, toexplain aspects of the present description. As used herein, the term“and/or” includes any and all combinations of one or more of theassociated listed items. Expressions such as “at least one of,” whenpreceding a list of elements, modify the entire list of elements and donot modify the individual elements of the list.

A heterocyclic compound according to an embodiment may be represented byFormula 1:

L₁ and L₂ in Formula 1 may each independently be a substituted orunsubstituted C₅-C₆₀ carbocyclic group or a substituted or unsubstitutedC₁-C₆₀ heterocyclic group.

In one embodiment, L₁ and L₂ may each independently be selected from:

a benzene group, a naphthalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a naphthofluorene group,a pyridine group, a pyrimidine group, a pyridazine group, a triazinegroup, a pyrrole group, a thiophene group, a furan group, an imidazolegroup, a pyrazole group, an oxazole group, an isoxazole group, athiazole group, an isoxazole group, a triazole group, a carbazole group,a dibenzofuran group, a benzonaphthofuran group, a dibenzothiophenegroup, a benzocarbazole group, and a dibenzocarbazole group; and

a benzene group, a naphthalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a naphthofluorene group,a pyridine group, a pyrimidine group, a pyridazine group, a triazinegroup, a pyrrole group, a thiophene group, a furan group, an imidazolegroup, a pyrazole group, an oxazole group, an isoxazole group, athiazole group, an isoxazole group, a triazole group, a carbazole group,a dibenzofuran group, a benzonaphthofuran group, a dibenzothiophenegroup, a benzocarbazole group, and a dibenzocarbazole group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a methyl group, an ethyl group, apropyl group, an isobutyl group, a sec-butyl group, a ter-butyl group, apentyl group, an iso-amyl group, a hexyl group, a C₁-C₂₀ alkoxy group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclopentenyl group, a cyclohexenyl group, a phenyl group, a naphthylgroup, a fluorenyl group, a carbazolyl group, a dibenzofuranyl group, abenzonaphthofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, and a dibenzocarbazolyl group.

In one or more embodiments, L₁ may be selected from groups representedby Formulae 3-1 to 3-15:

In Formulae 3-1 to 3-15,

Z₁ may be selected from hydrogen, deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid group ora salt thereof, a sulfonic acid group or a salt thereof, a phosphoricacid group or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxygroup, a phenyl group, a biphenyl group, a terphenyl group, a naphthylgroup, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenylgroup, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenylgroup, a pyrenyl group, a chrysenyl group, a pyridinyl group, apyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinylgroup, an isoquinolinyl group, a quinoxalinyl group, a quinazolinylgroup, a carbazolyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a triazinyl group, a benzimidazolyl group, a phenanthrolinylgroup, a biphenyl group, and a terphenyl group,

d2 may be an integer from 0 to 2,

d3 may be an integer from 0 to 3,

d4 may be an integer from 0 to 4, and

* and *′ each indicate a binding site to a neighboring atom.

In one embodiment, L₂ may be selected from groups represented byFormulae 3-1 to 3-58:

Y₁ in Formulae 3-1 to 3-58 may be O, S, C(Z₃)(Z₄), N(Z₅), or Si(Z₆)(Z₇).

In Formulae 3-1 to 3-58, Z₁ to Z₇ may each independently be selectedfrom hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid group or a salt thereof, asulfonic acid group or a salt thereof, a phosphoric acid group or a saltthereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, abiphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group,a spiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, achrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group,a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, a dibenzothiophenyl group, a triazinyl group, abenzimidazolyl group, a phenanthrolinyl group, a biphenyl group, and aterphenyl group,

Z₃ and Z₄ may optionally be linked to form a Spiro structure,

Z₆ and Z₇ may optionally be linked to form a Spiro structure,

d2 may be an integer from 0 to 2,

d3 may be an integer from 0 to 3,

d4 may be an integer from 0 to 4,

d5 may be an integer from 0 to 5,

d6 may be an integer from 0 to 6,

d8 may be an integer from 0 to 8, and

* and *′ each indicate a binding site to a neighboring atom.

R₁ and R₃ to R₁₀ in Formula 1 may each independently be selected fromhydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, —Si(Q₃₁)(Q₃₂)(Q₃₃), P(═O)(Q₃₁)(Q₃₂), a substituted orunsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀alkenyl group, a substituted or unsubstituted C₂-C₆₀ alkynyl group, asubstituted or unsubstituted C₁-C₆₀ alkoxy group, a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedheterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,a biphenyl group, and a terphenyl group.

In one embodiment, R₁ and R₃ to R₁₀ may each independently be selectedfrom:

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, —Si(Q₃₁)(Q₃₂)(Q₃₃), a methyl group, an ethyl group, apropyl group, an isobutyl group, a sec-butyl group, a ter-butyl group, apentyl group, an iso-amyl group, a hexyl group, a C₁-C₂₀ alkoxy group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclopentenyl group, a cyclohexenyl group, a phenyl group, a naphthylgroup, a fluorenyl group, a spiro-bifluorenyl group, aspiro-fluorene-benzofluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a pyrenyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyridinyl group, a pyrimidyl group, a quinolinylgroup, an isoquinolinyl group, a benzoquinolinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a biphenyl group, and a terphenyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenylgroup, a spiro-fluorene-benzofluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a pyrenyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyridinyl group, a pyrimidyl group, a quinolinylgroup, an isoquinolinyl group, a benzoquinolinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a biphenyl group, and a terphenyl group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, —Si(Q₃₁)(Q₃₂)(Q₃₃), a methyl group,an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, ater-butyl group, a pentyl group, an iso-amyl group, a hexyl group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclopentenyl group; a cyclohexenyl group, a phenyl group, a naphthylgroup, a fluorenyl group, a spiro-bifluorenyl group, aspiro-fluorene-benzofluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a pyrenyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyridinyl group, a pyrimidyl group, a quinolinylgroup, an isoquinolinyl group, a benzoquinolinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a biphenyl group, and a terphenyl group.

In one or more embodiments, R₁ may be selected from:

hydrogen, deuterium, a phenyl group, a naphthyl group, a fluorenylgroup, a pyrenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyridinyl group, a pyrimidyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a carbazolyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abiphenyl group, and a terphenyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a pyrenyl group, aphenalenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyridinyl group, apyrimidyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a naphthyridinyl group, a quinoxalinyl group, aquinazolinyl group, a carbazolyl group, a phenanthridinyl group, anacridinyl group, a phenanthrolinyl group, a phenazinyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abiphenyl group, and a terphenyl group, each substituted with at leastone selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, —Si(Q₃₁)(Q₃₂)(Q₃₃), a methyl group, an ethyl group, a propylgroup, an isobutyl group, a sec-butyl group, a ter-butyl group, a pentylgroup, an iso-amyl group, a hexyl group, a cyclopentyl group, acyclohexyl group, a cycloheptyl group, a cyclopentenyl group, acyclohexenyl group, a phenyl group, a naphthyl group, a fluorenyl group,a pyrenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyridinyl group, a pyrimidyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a carbazolyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abiphenyl group, and a terphenyl group, and

Q₃₁ to Q₃₃ may each independently be selected from hydrogen, deuterium,—F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, anamidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkylgroup, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryl group substituted with a C₁-C₆₀ alkylgroup, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensedpolycyclic group, a monovalent non-aromatic condensed heteropolycyclicgroup, a biphenyl group, and a terphenyl group.

In one or more embodiments, R₁ may be selected from groups representedby Formulae A-1 to A-15:

In Formulae A-1 to A-15,

Z₃₁ and Z₃₂ may each independently be selected from hydrogen, deuterium,—F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, anamidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkylgroup, a C₁-C₂₀ alkenyl group, a C₁-C₂₀ alkynyl group, a C₁-C₂₀ alkoxygroup, a phenyl group, a biphenyl group, a terphenyl group, a naphthylgroup, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, apyrenyl group, a chrysenyl group, a pyridinyl group, a pyrazinyl group,a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, anisoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, acarbazolyl group, a triazinyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂),—B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂),

Q₃₁ to Q₃₃ are each independently selected from a C₁-C₁₀ alkyl group, aC₁-C₁₀ alkoxy group, a phenyl group, a phenyl group substituted with aC₁-C₁₀ alkyl group, a biphenyl group, a terphenyl group, a naphthylgroup, a carbazolyl group, a dibenzofuranyl group, and adibenzothiophenyl group,

e3 is an integer from 1 to 3,

e4 is an integer from 1 to 4,

e5 is an integer from 1 to 5,

e6 is an integer from 1 to 6,

e7 is an integer from 1 to 7,

e9 is an integer from 1 to 9, and

* indicates a binding site to a neighboring atom.

In one embodiment, Z₃₁ and Z₃₂ may each independently be hydrogen or aphenyl group.

In one embodiment, R₁ may be selected from the following structures:

In the above structures,

* indicates a binding site to a neighboring atom.

In one embodiment, R₂ may be (i) a C₆-C₆₀ aryl group substituted with atleast one electron withdrawing group or (ii) a substituted orunsubstituted π electron-depleted nitrogen-containing ring group.

In one embodiment, the electron withdrawing group may be —F, —Cl, —Br,—I, a cyano group, or a C₁-C₂₀ fluoroalkyl group, but embodiments of thepresent disclosure, are not limited thereto.

In one or more embodiments, the electron withdrawing group may be —F,—Cl, a cyano group, —CF₃, or —CF₂CF₃, but embodiments of the presentdisclosure are not limited thereto.

In one embodiment, the “π electron-depleted nitrogen-containing ring”refers to a C₁-C₆₀ heterocyclic group having at least one *—N═*′ moietyas a ring-forming moiety.

For example, the “π electron-depleted nitrogen-containing ring” may bei) a 5-membered to 7-membered heteromonocyclic group having at least one*—N═*′ moiety, ii) a heteropolycyclic group in which two or more5-membered to 7-membered heteromonocyclic groups each having at leastone *—N═*′ moiety are condensed with each other, or iii) aheteropolycyclic group in which at least one of 5-membered to 7-memberedheteromonocyclic groups, each having at least one *—N═*′ moiety, iscondensed with at least one C₅-C₆₀ carbocyclic group.

Examples of the π electron-depleted nitrogen-containing ring include animidazole, a pyrazole, a thiazole, an isothiazole, an oxazole, anisoxazole, a pyridine, a pyrazine, a pyrimidine, a pyridazine, anindazole, a purine, a quinoline, an isoquinoline, a benzoquinoline, aphthalazine, a naphthyridine, a quinoxaline, a quinazoline, a cinnoline,a phenanthridine, an acridine, a phenanthroline, a phenazine, abenzimidazole, an isobenzothiazole, a benzoxazole, an isobenzoxazole, atriazole, a tetrazole, an oxadiazole, a triazine, a thiadiazole, animidazopyridine, an imidazopyrimidine, and an azacarbazole, butembodiments of the present disclosure are not limited thereto.

In one embodiment, R₂ may be represented by Formula 2.

In Formula 2, X₁ may be N or CAr₁,

X₂ may be N or CAr₂,

X₃ may be N or CAr₃,

X₄ may be N or CAr₄,

X₅ may be N or CAr₅, and

* indicates a binding site to a neighboring atom.

In Formula 2, Ar₁ to Ar₅ may each independently be selected fromhydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, —Si(Q₃₁)(Q₃₂)(Q₃₃), P(═O)(Q₃₁)(Q₃₂), a substituted orunsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀alkenyl group, a substituted or unsubstituted C₂-C₆₀ alkynyl group, asubstituted or unsubstituted C₁-C₆₀ alkoxy group, a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, and a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,and Ar₁ to Ar₅ may optionally be linked to form a substituted orunsubstituted ring,

provided that (i) at least one of X₁ to X₅ may be N, or (ii) at leastone of Ar₁ to Ar₅ may be a substituted or unsubstituted πelectron-depleted nitrogen-containing ring group or an electronwithdrawing group, and

Q₃₁ to Q₃₃ may each independently be selected from hydrogen, deuterium,—F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, anamidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkylgroup, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxygroup, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, aC₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₆-C₆₀ aryl group substituted with a C₁-C₆₀ alkyl group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup, a monovalent non-aromatic condensed heteropolycyclic group, abiphenyl group, and a terphenyl group.

In one embodiment, Ar₁ to Ar₅ may each independently be selected fromhydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, —Si(Q₃₁)(Q₃₂)(Q₃₃), a substituted or unsubstituted C₁-C₆₀alkyl group, a substituted or unsubstituted C₆-C₆₀ aryl group, and asubstituted or unsubstituted C₁-C₆₀ heteroaryl group.

In one or more embodiments, R₂ may be selected from groups representedby Formulae W-1 to W-16 and N-1 to N-59:

R_(w) in Formulae W-1 to W-16 may be selected from a cyano group, aC₁-C₂₀ fluoroalkyl group, and groups represented by Formulae N-1 toN-59.

In Formulae W-1 to W-16 and N-1 to N-59, Z₅₁ and Z₅₂ may eachindependently be selected from hydrogen, deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀fluoroalkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenylgroup, a terphenyl group, a naphthyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, an imidazolyl group, a pyrazole group, a thiazolyl group,an isothiazolyl group, an oxazolyl group, an isoxazolyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group, a dibenzofuranyl group, adibenzothiophenyl group, a triazinyl group, an indazolyl group, apurinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, acinnolinyl group, a phenanthridinyl group, an acridinyl group, aphenanthrolinyl group, a phenazinyl group, a benzimidazolyl group, anisobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group,a triazolyl group, a tetrazolyl group, an oxadiazolyl group, athiadiazolyl group, an imidazopyridinyl group, an imidazopyrimidinylgroup, and an azacarbazolyl group,

g2 may be an integer from 0 to 2,

g3 may be an integer from 0 to 3,

g4 may be an integer from 0 to 4,

g5 may be an integer from 0 to 5,

g6 may be an integer from 0 to 6, and

* indicates a binding site to a neighboring atom.

In one embodiment, R₂ may be selected from the following structures:

In the above structures,

* indicates a binding site to a neighboring atom.

In one embodiment, -(L₂)_(a2)-(R₂)_(b2) may be selected from thefollowing structures:

In the above structures,

* indicates a binding site to a neighboring atom.

In one embodiment, R₃ to R₁₀ may each independently be selected from:

hydrogen, deuterium, a phenyl group, a naphthyl group, a fluorenylgroup, a pyrenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyridinyl group, a pyrimidyl group, a quinolinyl group, an Isoquinolinylgroup, a benzoquinolinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a carbazolyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abiphenyl group, and a terphenyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a pyrenyl group, aphenalenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyridinyl group, apyrimidyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a naphthyridinyl group, a quinoxalinyl group, aquinazolinyl group, a carbazolyl group, a phenanthridinyl group, anacridinyl group, a phenanthrolinyl group, a phenazinyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abiphenyl group, and a terphenyl group, each substituted with at leastone selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, —Si(Q₃₁)(Q₃₂)(Q₃₃), a methyl group, an ethyl group, a propylgroup, an isobutyl group, a sec-butyl group, a ter-butyl group, a pentylgroup, an Iso-amyl group, a hexyl group, a cyclopentyl group, acyclohexyl group, a cycloheptyl group, a cyclopentenyl group, acyclohexenyl group, a phenyl group, a naphthyl group, a fluorenyl group,a pyrenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyridinyl group, a pyrimidyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a carbazolyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abiphenyl group, and a terphenyl group, and

Q₃₁ to Q₃₃ may each independently be selected from hydrogen, deuterium,—F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, anamidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkylgroup, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryl group substituted with a C₁-C₆₀ alkylgroup, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensedpolycyclic group, a monovalent non-aromatic condensed heteropolycyclicgroup, a biphenyl group, and a terphenyl group.

In one or more embodiments, R₃ to R₁₀ may each independently be selectedfrom hydrogen or the following structures:

In the above structures,

* indicates a binding site to a neighboring atom.

In one embodiment, at least one of R₄ and R₉ may be selected from:

a phenyl group, a naphthyl group, a fluorenyl group, a pyrenyl group, aphenalenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyridinyl group, apyrimidyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a naphthyridinyl group, a quinoxalinyl group, aquinazolinyl group, a carbazolyl group, a phenanthridinyl group, anacridinyl group, a phenanthrolinyl group, a phenazinyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abiphenyl group, and a terphenyl group; and

a phenyl group, a naphthyl group, a fluorenyl group, a pyrenyl group, aphenalenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyridinyl group, apyrimidyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a naphthyridinyl group, a quinoxalinyl group, aquinazolinyl group, a carbazolyl group, a phenanthridinyl group, anacridinyl group, a phenanthrolinyl group, a phenazinyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abiphenyl group, and a terphenyl group, each substituted with at leastone selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, a methyl group, an ethyl group, a propyl group, anisobutyl group, a sec-butyl group, a ter-butyl group, a pentyl group, aniso-amyl group, a hexyl group, a cyclopentyl group, a cyclohexyl group,a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, aphenyl group, a naphthyl group, a pyridinyl group, a pyrimidyl group, aquinolinyl group, an isoquinolinyl group, a quinoxalinyl group, aquinazolinyl group, a triazinyl group, a biphenyl group, and a terphenylgroup.

In one or more embodiments, R₄ and R₉ may each independently be selectedfrom the following structures:

In the above structures,

* indicates a binding site to a neighboring atom.

In one embodiment, R₃, R₅ to R₈, and R₁₀ may each independently beselected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, —Si(Q₃₁)(Q₃₂)(Q₃₃), a methyl group, an ethyl group, apropyl group, an isobutyl group, a sec-butyl group, a ter-butyl group, apentyl group, an iso-amyl group, and a hexyl group, and

Q₃₁ to Q₃₃ may each independently be selected from hydrogen, deuterium,—F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, anamidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkylgroup, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryl group substituted with a C₁-C₆₀ alkylgroup, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensedpolycyclic group, a monovalent non-aromatic condensed heteropolycyclicgroup, a biphenyl group, and a terphenyl group.

In one embodiment, R₃, R₅ to R₈, and R₁₀ may each be hydrogen (e.g., R₃,R₅ to R₈, and R₁₀ may all be hydrogen).

In one embodiment, the heterocyclic compound may be one of the followingcompounds, but embodiments of the present disclosure are not limitedthereto:

The heterocyclic compound represented by Formula 1 is a compound havinga structure in which a substituent having an electron withdrawingproperty is N-substituted in a phenophosphazine core. Since theheterocyclic compound has a phosphine oxide (P═O) structure, tripletenergy thereof is high. Thus, the heterocyclic compound may be variouslyapplied as a phosphorescent material (e.g., the heterocyclic compoundmay be used as a phosphorescent material in various suitableapplications). While a compound that is similar to the heterocycliccompound but has no phosphine oxide structure emits green light, theheterocyclic compound according to embodiments of the present disclosureemits blue light.

Since the phosphine oxide core itself has high triplet energy, theheterocyclic compound may be variously applied as a phosphorescentmaterial (e.g., the heterocyclic compound may be used as aphosphorescent material in various suitable applications). However, whenthe heterocyclic compound is applied to a device as a host, electroncharacteristics are low, and thus a driving voltage greatly increases.Therefore, in order to prevent such a phenomenon (or to reduce alikelihood or degree of such a phenomenon), the heterocyclic compound isimparted with bipolar characteristics. To this end, electroncharacteristics may be supplemented by using a structure in which asubstituent having an electron withdrawing property is N-substituted,like the heterocyclic compound. As a result, when the heterocycliccompound is applied to a device, a driving voltage, efficiency, andlifespan of the device may be improved.

Therefore, an electronic device, for example, an organic light-emittingdevice, which includes the heterocyclic compound represented by Formula1, may have a low driving voltage, high current density, and highefficiency.

A synthesis method for the heterocyclic compound represented by Formula1 would be apparent to those of ordinary skill in the art by referringto the following examples.

At least one of the heterocyclic compound of Formula 1 may be usedbetween a pair of electrodes of an organic light-emitting device. Forexample, the heterocyclic compound may be included in at least one layerselected from a hole transport region and an emission layer. In one ormore embodiments, the heterocyclic compound of Formula 1 may be used asa material for a capping layer located outside of a pair of electrodesof an organic light-emitting device.

According to another aspect of embodiments, an organic light-emittingdevice includes: a first electrode, a second electrode, and an organiclayer between the first electrode and the second electrode, the organiclayer including an emission layer and at least one heterocyclic compoundrepresented by Formula 1 described above.

The expression “(an organic layer) includes at least one of theheterocyclic compounds,” as used herein, may include a case in which“(an organic layer) includes identical heterocyclic compoundsrepresented by Formula 1” and a case in which “(an organic layer)includes two or more different heterocyclic compounds represented byFormula 1.”

For example, the organic layer may include, as the heterocycliccompound, Compound 1 alone. In this regard, Compound 1 may exist in anemission layer of the organic light-emitting device. In one or moreembodiments, the organic layer may include, as the heterocycliccompound, Compound 1 and Compound 2. In this regard, Compound 1 andCompound 2 may exist in an identical layer (for example, Compound 1 andCompound 2 may all exist in an emission layer), or different layers (forexample, Compound 1 may exist in an emission layer and Compound 2 mayexist in an electron transport layer).

According to one embodiment,

the first electrode of the organic light-emitting device may be ananode,

the second electrode of the organic light-emitting device may be acathode,

the organic layer of the organic light-emitting device may furtherinclude a hole transport region between the first electrode and theemission layer and an electron transport region between the emissionlayer and the second electrode,

the hole transport region may include at least one layer selected from ahole injection layer, a hole transport layer, a buffer layer, anemission auxiliary layer, and an electron blocking layer, and

the electron transport region may include an electron transport regionincluding at least one selected from a hole blocking layer, an electrontransport layer, and an electron injection layer. Herein, theheterocyclic compound represented by Formula 1 may be included in theelectron transport region.

In one embodiment, the electron transport region of the organiclight-emitting device may include an electron transport layer and anelectron injection layer, and at least one of the electron transportlayer and the electron injection layer may include the heterocycliccompound represented by Formula 1. However, embodiments of the presentdisclosure are not limited thereto.

At least one layer selected from the electron transport layer and theelectron injection layer may include an alkali metal, an alkaline earthmetal, a rare earth metal, an alkali metal compound, an alkalineearth-metal compound, a rare earth metal compound, an alkali metalcomplex, an alkaline earth-metal complex, a rare earth metal complex, orany combinations thereof. As used herein, the terms “combinationthereof” and “combinations thereof” may refer to a chemical combination(e.g., an alloy or chemical compound), a mixture, or a laminatedstructure of components.

The emission layer in the organic light emitting device may include adopant and a host, and the host may include at least one selected froman anthracene-based compound, a pyrene-based compound, and aspiro-bifluorene-based compound.

The term “organic layer,” as used herein, refers to a single layerand/or a plurality of layers disposed between the first electrode andthe second electrode of the organic light-emitting device. A materialincluded in the “organic layer” is not limited to an organic material.

The accompanying drawing is a schematic view of an organiclight-emitting device 10 according to an embodiment. The organiclight-emitting device 10 includes a first electrode 110, an organiclayer 150, and a second electrode 190.

Hereinafter, the structure of the organic light-emitting device 10according to an embodiment and a method of manufacturing the organiclight-emitting device 10 will be described in connection with theaccompanying drawing.

In the accompanying drawing, a substrate may be additionally disposedunder the first electrode 110 or above the second electrode 190. Thesubstrate may be a glass substrate or a plastic substrate, each havingexcellent mechanical strength, thermal stability, transparency, surfacesmoothness, ease of handling, and water resistance.

The first electrode 110 may be formed by depositing or sputtering amaterial for forming the first electrode 110 on the substrate. When thefirst electrode 110 is an anode, the material for a first electrode maybe selected from materials with a high work function to facilitate holeinjection.

The first electrode 110 may be a reflective electrode, asemi-transmissive electrode, or a transmissive electrode. When the firstelectrode 110 is a transmissive electrode, a material for forming afirst electrode may be selected from indium tin oxide (ITO), indium zincoxide (IZO), tin oxide (SnO₂), zinc oxide (ZnO), and any combinationsthereof, but embodiments of the present disclosure are not limitedthereto. When the first electrode 110 is a semi-transmissive electrodeor a reflective electrode, as a material for forming the first electrode110, magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium(Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver(Mg—Ag), or any combination thereof may be used. However, the materialfor forming the first electrode 110 is not limited thereto.

The first electrode 110 may have a single-layered structure, or amulti-layered structure including two or more layers. For example, thefirst electrode 110 may have a three-layered structure of ITO/Ag/ITO,but the structure of the first electrode 110 is not limited thereto.

The organic layer 150 is disposed on the first electrode 110. Theorganic layer 150 may include an emission layer.

The organic layer 150 may further include a hole transport regionbetween the first electrode 110 and the emission layer, and an electrontransport region between the emission layer and the second electrode190.

The hole transport region may have i) a single-layered structureincluding a single layer including a single material, ii) asingle-layered structure including a single layer including a pluralityof different materials, or iii) a multi-layered structure having aplurality of layers including a plurality of different materials.

The hole transport region may include at least one layer selected from ahole injection layer (HIL), a hole transport layer (HTL), an emissionauxiliary layer, and an electron blocking layer (EBL).

For example, the hole transport region may have a single-layeredstructure including a single layer including a plurality of differentmaterials, or a multi-layered structure having a hole injectionlayer/hole transport layer structure, a hole injection layer/holetransport layer/emission auxiliary layer structure, a hole injectionlayer/emission auxiliary layer structure, a hole transportlayer/emission auxiliary layer structure, or a hole injection layer/holetransport layer/electron blocking layer structure, wherein for eachstructure, constituting layers are sequentially stacked from the firstelectrode 110 in this stated order, but the structure of the holetransport region is not limited thereto.

The hole transport region may include at least one selected fromm-MTDATA, TDATA, 2-TNATA, NPB(NPD), 13-NPB, TPD, Spiro-TPD, Spiro-NPB,methylated-NPB, TAPC, HMTPD, 4,4′,4″-tris(N-carbazolyl)triphenylamine(TCTA), polyaniline/dodecylbenzenesulfonic acid (PANI/DBSA),poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS),polyaniline/camphor sulfonic acid (PANI/CSA),polyaniline/poly(4-styrenesulfonate) (PANT/PSS), a compound representedby Formula 201, and a compound represented by Formula 202:

In Formulae 201 and 202,

L₂₀₁ to L₂₀₄ may each independently be selected from a substituted orunsubstituted C₃-C₁₀ cycloalkylene group, a substituted or unsubstitutedheterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

L₂₀₅ may be selected from *—O—*′, *—S—*′, *—N(Q₂₀₁)-*′, a substituted orunsubstituted C₁-C₂₀ alkylene group, a substituted or unsubstitutedC₂-C₂₀ alkenylene group, a substituted or unsubstituted C₃-C₁₀cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

xa1 to xa4 may each independently be an integer from 0 to 3,

xa5 may be an integer from 1 to 10,

R₂₀₁ to R₂₀₄ and Q₂₀₁ may each independently be selected from asubstituted or unsubstituted C₃-C₁₀ cycloalkyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkyl group, a substituted orunsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀aryl group, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, and a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group.

In one embodiment, in Formula 202, R₂₀₁ and R₂₀₂ may optionally belinked via a single bond, a dimethyl-methylene group, or adiphenyl-methylene group, and R₂₀₃ and R₂₀₄ may optionally be linked viaa single bond, a dimethyl-methylene group, or a diphenyl-methylenegroup.

In one embodiment, in Formulae 201 and 202,

L₂₀₁ to L₂₀₅ may each independently be selected from:

a phenylene group, a pentalenylene group, an indenylene group, anaphthylene group, an azulenylene group, a heptalenylene group, anindacenylene group, an acenaphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenalenylene group, a phenanthrenylenegroup, an anthracenylene group, a fluoranthenylene group, atriphenylenylene group, a pyrenylene group, a chrysenylene group, anaphthacenylene group, a picenylene group, a perylenylene group, apentaphenylene group, a hexacenylene group, a pentacenylene group, arubicenylene group, a coronenylene group, an ovalenylene group, athiophenylene group, a furanylene group, a carbazolylene group, anindolylene group, an isoindolylene group, a benzofuranylene group, abenzothiophenylene group, a dibenzofuranylene group, adibenzothiophenylene group, a benzocarbazolylene group, adibenzocarbazolylene group, a dibenzosilolylene group, and apyridinylene group; and

a phenylene group, a pentalenylene group, an indenylene group, anaphthylene group, an azulenylene group, a heptalenylene group, anindacenylene group, an acenaphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenalenylene group, a phenanthrenylenegroup, an anthracenylene group, a fluoranthenylene group, atriphenylenylene group, a pyrenylene group, a chrysenylene group, anaphthacenylene group, a picenylene group, a perylenylene group, apentaphenylene group, a hexacenylene group, a pentacenylene group, arubicenylene group, a coronenylene group, an ovalenylene group, athiophenylene group, a furanylene group, a carbazolylene group, anindolylene group, an isoindolylene group, a benzofuranylene group, abenzothiophenylene group, a dibenzofuranylene group, adibenzothiophenylene group, a benzocarbazolylene group, adibenzocarbazolylene group, a dibenzosilolylene group, and apyridinylene group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, a heptalenyl group, an indacenyl group, an acenaphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, an indolyl group,an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinylgroup, —Si(Q₃₁)(Q₃₂)(Q₃₃), and —N(Q₃₁)(Q₃₂); and

Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

In one or more embodiments, xa1 to xa4 may each independently be 0, 1 or2.

In one or more embodiments, xa5 may be 1, 2, 3, or 4.

In one or more embodiments, R₂₀₁ to R₂₀₄ and Q₂₀₁ may each independentlybe selected from a phenyl group, a biphenyl group, a terphenyl group, apentalenyl group, an indenyl group, a naphthyl group, an azulenyl group,a heptalenyl group, an indacenyl group, an acenaphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, an indolyl group,an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, and apyridinyl group;

a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group,an indenyl group, a naphthyl group, an azulenyl group, a heptalenylgroup, an indacenyl group, an acenaphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenalenyl group, a phenanthrenyl group, an anthracenyl group,a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, achrysenyl group, a naphthacenyl group, a picenyl group, a perylenylgroup, a pentaphenyl group, a hexacenyl group, a pentacenyl group, arubicenyl group, a coronenyl group, an ovalenyl group, a thiophenylgroup, a furanyl group, a carbazolyl group, an indolyl group, anisoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, and apyridinyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, a heptalenyl group, an indacenyl group, an acenaphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, an indolyl group,an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinylgroup, —Si(Q₃₁)(Q₃₂)(Q₃₃), and —N(Q₃₁)(Q₃₂); and

Q₃₁ to Q₃₃ are the same as described above.

In one or more embodiments, at least one selected from R₂₀₁ to R₂₀₃ inFormula 201 may each independently be selected from:

a fluorenyl group, a spiro-bifluorenyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group; and

a fluorenyl group, a spiro-bifluorenyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group, each substitutedwith at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a phenyl group substituted with a C₁-C₁₀ alkylgroup, a phenyl group substituted with —F, a naphthyl group, a fluorenylgroup, a spiro-bifluorenyl group, a carbazolyl group, a dibenzofuranylgroup, and a dibenzothiophenyl group;

but embodiments of the present disclosure are not limited thereto.

In one or more embodiments, in Formula 202, i) R₂₀₁ and R₂₀₂ may belinked via a single bond, and/or ii) R₂₀₃ and R₂₀₄ may be linked via asingle bond.

In one or more embodiments, at least one selected from R₂₀₁ to R₂₀₄ inFormula 202 may be selected from:

a carbazolyl group; and

a carbazolyl group, substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, acarbazolyl group, a dibenzofuranyl group, and a dibenzothiophenyl group;

but embodiments of the present disclosure are not limited thereto.

The compound represented by Formula 201 may be represented by Formula201A:

In one embodiment, the compound represented by Formula 201 may berepresented by Formula 201A(1) below, but embodiments of the presentdisclosure are not limited thereto:

In one embodiment, the compound represented by Formula 201 may berepresented by Formula 201A-1 below, but embodiments of the presentdisclosure are not limited thereto:

In one embodiment, the compound represented by Formula 202 may berepresented by Formula 202A:

In one embodiment, the compound represented by Formula 202 may berepresented by Formula 202A-1:

In Formulae 201A, 201A(1), 201A-1, 202A, and 202A-1,

L₂₀₁ to L₂₀₃, xa1 to xa3, xa5 and R₂₀₂ to R₂₀₄ are the same as describedabove,

R₂₁₁ and R₂₁₂ are the same as described in connection with R₂₀₃,

R₂₁₃ to R₂₁₇ may each independently be selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, a heptalenyl group, an indacenyl group, an acenaphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, an indolyl group,an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, and apyridinyl group.

The hole transport region may include at least one compound selectedfrom Compounds HT1 to HT39, but embodiments of the present disclosureare not limited thereto:

A thickness of the hole transport region may be in a range of about 100Å to about 10,000 Å, for example, about 100 Å to about 1,000 Å. When thehole transport region includes at least one of a hole injection layerand a hole transport layer, a thickness of the hole injection layer maybe in a range of about 100 Å to about 9,000 Å, for example, about 100 Åto about 1,000 Å, and a thickness of the hole transport layer may be ina range of about 50 Å to about 2,000 Å, for example about 100 Å to about1,500 Å. When the thicknesses of the hole transport region, the holeinjection layer and the hole transport layer are within these ranges,suitable or satisfactory hole transporting characteristics may beobtained without a substantial increase in driving voltage.

The emission auxiliary layer may increase light-emission efficiency bycompensating for an optical resonance distance according to thewavelength of light emitted by an emission layer, and the electronblocking layer may block the flow of electrons from an electrontransport region. The emission auxiliary layer and the electron blockinglayer may include the materials as described above.

The hole transport region may further include, in addition to thesematerials, a charge-generation material for the improvement ofconductive properties. The charge-generation material may behomogeneously or non-homogeneously dispersed in the hole transportregion.

The charge-generation material may be, for example, a p-dopant.

In one embodiment, a lowest unoccupied molecular orbital (LUMO) energylevel of the p-dopant may be −3.5 eV or less.

The p-dopant may include at least one selected from a quinonederivative, a metal oxide, and a cyano group-containing compound, butembodiments of the present disclosure are not limited thereto.

For example, the p-dopant may include at least one selected from:

a quinone derivative, such as tetracyanoquinodimethane (TCNQ) or2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ);

a metal oxide, such as tungsten oxide or molybdenum oxide;

1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile (HAT-CN); and

a compound represented by Formula 221 below:

but embodiments of the present disclosure are not limited thereto:

In Formula 221,

R₂₂₁ to R₂₂₃ may each independently be selected from a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedheterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₁-C₆₀ heteroaryl group, asubstituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted monovalentnon-aromatic condensed heteropolycyclic group, and at least one selectedfrom R₂₂₁ to R₂₂₃ may have at least one substituent selected from acyano group, —F, —Cl, —Br, —I, a C₁-C₂₀ alkyl group substituted with —F,a C₁-C₂₀ alkyl group substituted with —Cl, a C₁-C₂₀ alkyl groupsubstituted with Br, and a C₁-C₂₀ alkyl group substituted with —I.

When the organic light-emitting device 10 is a full-color organiclight-emitting device, the emission layer may be patterned into a redemission layer, a green emission layer, or a blue emission layer,according to a sub-pixel. In one or more embodiments, the emission layermay have a stacked structure of two or more layers selected from a redemission layer, a green emission layer, and a blue emission layer, inwhich the two or more layers contact each other or are separated fromeach other. In one or more embodiments, the emission layer may includetwo or more materials selected from a red light-emitting material, agreen light-emitting material, and a blue light-emitting material, inwhich the two or more materials are mixed with each other in a singlelayer to emit white light.

The emission layer may include a host and a dopant. The dopant mayinclude at least one selected from a phosphorescent dopant and afluorescent dopant.

An amount of the dopant in the emission layer may be, in general, in arange of about 0.01 parts by weight to about 15 parts by weight based on100 parts by weight of the host, but embodiments of the presentdisclosure are not limited thereto.

A thickness of the emission layer may be in a range of about 100 Å toabout 1,000 Å, for example, about 200 Å to about 600 Å. When thethickness of the emission layer is within this range, excellentlight-emission characteristics may be obtained without a substantialincrease in driving voltage.

In one or more embodiments, the host may include a compound representedby Formula 301:[Ar₃₀₁]_(xb11)-[(L₃₀₁)_(xb1)-R₃₀₁]_(xb21).  Formula 301

In Formula 301,

Ar₃₀₁ may be a substituted or unsubstituted C₅-C₆₀ carbocyclic group ora substituted or unsubstituted C₁-C₆₀ heterocyclic group,

xb11 may be 1, 2, or 3; and

L₃₀₁ may be selected from a substituted or unsubstituted C₃-C₁₀cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

xb1 may be an integer from 0 to 5,

R₃₀₁ may be selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group,a cyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a substituted or unsubstituted C₁-C₆₀ alkyl group, asubstituted or unsubstituted C₂-C₆₀ alkenyl group, a substituted orunsubstituted C₂-C₆₀ alkynyl group, a substituted or unsubstitutedC₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀ cycloalkylgroup, a substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted heterocycloalkenyl group, a substituted or unsubstitutedC₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀ aryloxy group,a substituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,—Si(Q₃₀₁)(Q₃₀₂)(Q₃₀₃), —N(Q₃₀₁)(Q₃₀₂), —B(Q₃₀₁)(Q₃₀₂), —C(═O)(Q₃₀₁),—S(═O)₂(Q₃₀₁), and —P(═O)(Q₃₀₁)(Q₃₀₂),

xb21 may be an integer from 1 to 5, and

Q₃₀₁ to Q₃₀₃ may each independently be selected from a C₁-C₁₀ alkylgroup, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, and a naphthyl group, but embodiments of the presentdisclosure are not limited thereto.

In one embodiment, in Formula 301, Ar₃₀₁ may be selected from:

a naphthalene group, a fluorene group, a spiro-bifluorene group, abenzofluorene group, a dibenzofluorene group, a phenalene group, aphenanthrene group, an anthracene group, a fluoranthene group, atriphenylene group, a pyrene group, a chrysene group, a naphthacenegroup, a picene group, a perylene group, a pentaphene group, anindenoanthracene group, a dibenzofuran group, and a dibenzothiophenegroup;

a naphthalene group, a fluorene group, a spiro-bifluorene group, abenzofluorene group, a dibenzofluorene group, a phenalene group, aphenanthrene group, an anthracene group, a fluoranthene group, atriphenylene group, a pyrene group, a chrysene group, a naphthacenegroup, a picene group, a perylene group, a pentaphene group, anindenoanthracene group, a dibenzofuran group, and a dibenzothiophenegroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, a naphthyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂),—C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂); and

Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group, but embodiments of the present disclosureare not limited thereto.

When xb11 in Formula 301 is two or more, two or more Ar₃₀₁(s) may belinked via a single bond.

In one or more embodiments, the compound represented by Formula 301 maybe represented by Formula 301-1 or 301-2:

In Formulae 301-1 and 301-2,

A₃₀₁ to A₃₀₄ may each independently be selected from a benzene group, anaphthalene group, a phenanthrene group, a fluoranthene group, atriphenylene group, a pyrene group, a chrysene group, a pyridine group,a pyrimidine group, an indene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,an indole group, a carbazole group, a benzocarbazole group,dibenzocarbazole group, a furan group, a benzofuran group, adibenzofuran group, a naphthofuran group, a benzonaphthofuran group,dinaphthofuran group, a thiophene group, a benzothiophene group, adibenzothiophene group, a naphthothiophene group, abenzonaphthothiophene group, and a dinaphthothiophene group,

X₃₀₁ is O, S, or N-[(L₃₀₄)_(xb4)-R₃₀₄],

R₃₁₁ to R₃₁₄ may each independently be selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂),—B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂),

xb22 and xb23 may each independently be 0, 1, or 2,

L₃₀₁, xb1, R₃₀₁, and Q₃₁ to Q₃₃ are the same as described above,

L₃₀₂ to L₃₀₄ may each independently be the same as described inconnection with L₃₀₁,

xb2 to xb4 may each independently be the same as described in connectionwith xb1, and

R₃₀₂ to R₃₀₄ may each independently be the same as described inconnection with R₃₀₁.

For example, L₃₀₁ to L₃₀₄ in Formulae 301, 301-1, and 301-2 may eachindependently be selected from:

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group;

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, anaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenylgroup, a hexacenyl group, a pentacenyl group, a thiophenyl group, afuranyl group, a carbazolyl group, an indolyl group, an isoindolylgroup, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranylgroup, a dibenzothiophenyl group, a benzocarbazolyl group, adibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, anoxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, abenzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinylgroup, an azacarbazolyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂),—B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ may be the same as described above.

In one embodiment, R₃₀₁ to R₃₀₄ in Formulae 301, 301-1 and 301-2 mayeach independently be selected from:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenanthrenyl group, an anthracenyl group, a fluoranthenylgroup, a triphenylenyl group, a pyrenyl group, a chrysenyl group, aperylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a thiophenyl group, a furanyl group, a carbazolyl group, anindolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolylgroup, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₃₁ and Q₃₃ may be the same as described above.

In one or more embodiments, the host may include an alkaline earth metalcomplex. For example, the host may be selected from a Be complex (forexample, Compound H55), a Mg complex, and a Zn complex.

The host may include at least one selected from9,10-di(2-naphthyl)anthracene (ADN),2-methyl-9,10-bis(naphthalen-2-yl)anthracene (MADN),9,10-di-(2-naphthyl)-2-t-butyl-anthracene (TBADN),4,4′-bis(N-carbazolyl)-1,1′-biphenyl (CBP), 1,3-di-9-carbazolylbenzene(mCP), 1,3,5-tri(carbazol-9-yl)benzene (TCP), and Compounds H1 to H55,but embodiments of the present disclosure are not limited thereto:

The phosphorescent dopant may include an organometallic complexrepresented by Formula 401 below:

In Formulae 401 and 402,

M may be selected from iridium (Ir), platinum (Pt), palladium (Pd),osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu),terbium (Tb), rhodium (Rh), and thulium (Tm),

L₄₀₁ may be selected from ligands represented by Formula 402, and xc1may be 1, 2, or 3, wherein, when xc1 is two or more, two or more L₄₀₁(s)may be identical to or different from each other,

L₄₀₂ may be an organic ligand, and xc2 may be an integer from 0 to 4,wherein, when xc2 is two or more, two or more L₄₀₂(s) may be identicalto or different from each other,

X₄₀₁ to X₄₀₄ may each independently be nitrogen or carbon,

X₄₀₁ and X₄₀₃ may be linked via a single bond or a double bond, and X₄₀₂and X₄₀₄ may be linked via a single bond or a double bond,

A₄₀₁ and A₄₀₂ may each independently be selected from a C₅-C₆₀carbocyclic group or a C₁-C₆₀ heterocyclic group,

X₄₀₅ may be a single bond, *—O—*′, *—S—*′, *—C(═O)—*′, *—N(Q₄₁₁)-*′,*—C(Q₄₁₁)(Q₄₁₂)-*′, *—C(Q₄₁₁)═C(Q₄₁₂)-*′, *—C(Q₄₁₁)-*′, or *═C(Q₄₁₁)═*′,and Q₄₁₁ and Q₄₁₂ are hydrogen, deuterium, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, or a naphthyl group,

X₄₀₆ may be a single bond, O, or S,

R₄₀₁ and R₄₀₂ may each independently be selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, asubstituted or unsubstituted C₁-C₂₀ alkyl group, a substituted orunsubstituted C₁-C₂₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkylgroup, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, asubstituted or unsubstituted heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, and asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group, —Si(Q₄₀₁)(Q₄₀₂)(Q₄₀₃), —N(Q₄₀₁)(Q₄₀₂),—B(Q₄₀₁)(Q₄₀₂), —C(═O)(Q₄₀₁), —S(═O)₂(Q₄₀₁), and —P(═O)(Q₄₀₁)(Q₄₀₂), andQ₄₀₁ to Q₄₀₃ may each independently selected from a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a C₆-C₂₀ aryl group, and a C₁-C₂₀ heteroarylgroup,

xc11 and xc12 may each independently be an integer from 0 to 10, and

* and *′ in Formula 402 each indicate a binding site to M in Formula401.

In one embodiment, A₄₀₁ and A₄₀₂ in Formula 402 may each independentlybe selected from a benzene group, a naphthalene group, a fluorene group,a spiro-bifluorene group, an indene group, a pyrrole group, a thiophenegroup, a furan group, an imidazole group, a pyrazole group, a thiazolegroup, an isothiazole group, an oxazole group, an isoxazole group, apyridine group, a pyrazine group, a pyrimidine group, a pyridazinegroup, a quinoline group, an isoquinoline group, a benzoquinoline group,a quinoxaline group, a quinazoline group, a carbazole group, abenzimidazole group, a benzofuran group, a benzothiophene group, anisobenzothiophene group, a benzoxazole group, an isobenzoxazole group, atriazole group, a tetrazole group, an oxadiazole group, a triazinegroup, a dibenzofuran group, and a dibenzothiophene group.

In one or more embodiments, in Formula 402, i) X₄₀₁ may be nitrogen, andX₄₀₂ may be carbon, or ii) X₄₀₁ and X₄₀₂ may each be nitrogen at thesame time (e.g., X₄₀₁ and X₄₀₂ may both be nitrogen).

In one or more embodiments, R₄₀₁ and R₄₀₂ in Formula 402 may eachindependently be selected from:

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxy group;

a C₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxy group, each substituted withat least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a phenyl group, a naphthyl group, acyclopentyl group, a cyclohexyl group, an adamantanyl group, anorbornanyl group, and a norbornenyl group;

a cyclopentyl group, a cyclohexyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a naphthyl group, a fluorenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group;

a cyclopentyl group, a cyclohexyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group a phenyl group, a biphenyl group,a terphenyl group, a naphthyl group, a fluorenyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, atriazinyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group, each substitutedwith at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, acyclopentyl group, a cyclohexyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a naphthyl group, a fluorenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group;

—Si(Q₄₀₁)(Q₄₀₂)(Q₄₀₃), —N(Q₄₀₁)(Q₄₀₂), —B(Q₄₀₁)(Q₄₀₂), —C(═O)(Q₄₀₁),—S(═O)₂(Q₄₀₁) and —P(═O)(Q₄O(Q₄₀₂); and

Q₄₀₁ to Q₄₀₃ may each independently be selected from a C₁-C₁₀ alkylgroup, a C1-C10 alkoxy group, a phenyl group, a biphenyl group, and anaphthyl group, but embodiments of the present disclosure are notlimited thereto.

In one or more embodiments, when xc1 in Formula 401 is two or more, twoA₄₀₁(s) in two or more L₄₀₁(s) may optionally be linked via X₄₀₇, whichis a linking group, and two A₄₀₂(s) may optionally be linked via X₄₀₈,which is a linking group (see Compounds PD1 to PD4 and PD7). X₄₀₇ andX₄₀₈ may each independently be a single bond, *—O—*′, *—S—*′,*—C(═O)—*′, *—N(Q₄₁₃)*′, *—C(Q₄₁₃)(Q₄₁₄)-*′, or *—C(Q₄₁₃)═C(Q₄₁₄)-*′(wherein Q₄₁₃ and Q₄₁₄ may each independently be hydrogen, deuterium, aC₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenylgroup, a terphenyl group, or a naphthyl group), but embodiments of thepresent disclosure are not limited thereto.

L₄₀₂ in Formula 401 may be a monovalent, divalent, or trivalent organicligand. For example, L₄₀₂ may be selected from halogen, diketone (forexample, acetylacetonate), carboxylic acid (for example, picolinate),—C(═O), isonitrile, —CN, and phosphorus (for example, phosphine, orphosphite), but embodiments of the present disclosure are not limitedthereto.

In one or more embodiments, the phosphorescent dopant may be selectedfrom, for example, Compounds PD1 to PD25, but embodiments of the presentdisclosure are not limited thereto:

The fluorescent dopant may include an arylamine compound or astyrylamine compound.

The fluorescent dopant may include a compound represented by Formula 501below.

In Formula 501,

Ar₅₀₁ may be a substituted or unsubstituted C₅-C₆₀ carbocyclic group ora substituted or unsubstituted C₁-C₆₀ heterocyclic group,

L₅₀₁ to L₅₀₃ may each independently be selected from a substituted orunsubstituted C₃-C₁₀ cycloalkylene group, a substituted or unsubstitutedheterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₆₀ heteroarylene group, asubstituted or unsubstituted divalent non-aromatic condensed polycyclicgroup, and a substituted or unsubstituted divalent non-aromaticcondensed heteropolycyclic group,

xd1 to xd3 may each independently be an integer of 0 to 3;

R₅₀₁ and R₅₀₂ may each independently be selected from a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, and a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,

xd4 may be an integer of 1 to 6.

In one embodiment, Ar₅₀₁ in Formula 501 may be selected from:

a naphthalene group, a heptalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, and an indenophenanthrenegroup; and

a naphthalene group, a heptalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, and an indenophenanthrenegroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

In one or more embodiments, L₅₀₁ to L₅₀₃ in Formula 501 may eachindependently be selected from:

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, each substituted with atleast one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, and a pyridinyl group.

In one or more embodiments, R₅₀₁ and R₅₀₂ in Formula 501 may eachindependently be selected from:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, and a pyridinyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, and a pyridinyl group, each substituted with atleast one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, and —Si(Q₃₁)(Q₃₂)(Q₃₃); and

Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

In one or more embodiments, xd4 in Formula 501 may be 2, but embodimentsof the present disclosure are not limited thereto.

For example, the fluorescent dopant may be selected from Compounds FD1to FD22:

In one or more embodiments, the fluorescent dopant may be selected fromthe following compounds, but embodiments of the present disclosure arenot limited thereto.

The electron transport region may have i) a single-layered structureincluding a single layer including a single material, ii) asingle-layered structure including a single layer including a pluralityof different materials, or iii) a multi-layered structure having aplurality of layers including a plurality of different materials.

The electron transport region may include at least one selected from abuffer layer, a hole blocking layer, an electron control layer, anelectron transport layer, and an electron injection layer, butembodiments of the present disclosure are not limited thereto.

For example, the electron transport region may have an electrontransport layer/electron injection layer structure, a hole blockinglayer/electron transport layer/electron injection layer structure, anelectron control layer/electron transport layer/electron injection layerstructure, or a buffer layer/electron transport layer/electron injectionlayer structure, wherein for each structure, constituting layers aresequentially stacked from an emission layer. However, embodiments of thestructure of the electron transport region are not limited thereto.

The electron transport region (for example, a buffer layer, a holeblocking layer, an electron control layer, or an electron transportlayer in the electron transport region) may include a metal-freecompound containing at least one π electron-depleted nitrogen-containingring.

The “π electron-depleted nitrogen-containing ring” indicates a C₁-C₆₀heterocyclic group having at least one *—N═*′ moiety as a ring-formingmoiety.

For example, the “π electron-depleted nitrogen-containing ring” may bei) a 5-membered to 7-membered heteromonocyclic group having at least one*—N═*′ moiety, ii) a heteropolycyclic group in which two or more5-membered to 7-membered heteromonocyclic groups each having at leastone *—N═*′ moiety are condensed with each other, or iii) aheteropolycyclic group in which at least one of 5-membered to 7-memberedheteromonocyclic groups, each having at least one *—N═*′ moiety, iscondensed with at least one C₅-C₆₀ carbocyclic group.

Examples of the π electron-depleted nitrogen-containing ring include animidazole, a pyrazole, a thiazole, an isothiazole, an oxazole, anisoxazole, a pyridine, a pyrazine, a pyrimidine, a pyridazine, anindazole, a purine, a quinoline, an isoquinoline, a benzoquinoline, aphthalazine, a naphthyridine, a quinoxaline, a quinazoline, a cinnoline,a phenanthridine, an acridine, a phenanthroline, a phenazine, abenzimidazole, an isobenzothiazole, a benzoxazole, an isobenzoxazole, atriazole, a tetrazole, an oxadiazole, a triazine, thiadiazole, animidazopyridine, an imidazopyrimidine, and an azacarbazole, butembodiments of the present disclosure are not limited thereto.

For example, the electron transport region may include a compoundrepresented by Formula 601:[Ar_(6O1)]_(xe11)-[(L₆₀₁)_(xe1)-R₆₀₁]_(xe21).  Formula 601

In Formula 601,

Ar₆₀₁ may be a substituted or unsubstituted C₅-C₆₀ carbocyclic group ora substituted or unsubstituted C₁-C₆₀ heterocyclic group,

xe11 may be 1, 2, or 3,

L₆₀₁ may be selected from a substituted or unsubstituted C₃-C₁₀cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

xe1 may be an integer from 0 to 5,

R₆₀₁ may be selected from a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkylgroup, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, asubstituted or unsubstituted C₆-C₆₀ aryl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, a substituted or unsubstituted monovalent non-aromaticcondensed heteropolycyclic group, —Si(Q₆₀₁)(Q₆₀₂)(Q₆₀₃), —C(═O)(Q₆₀₁),—S(═O)₂(Q₆₀₁), and —P(═O)(Q₆₀₁)(Q₆₀₂), and

Q₆₀₁ to Q₆₀₃ may each independently be a C₁-C₁₀ alkyl group, a C₁-C₁₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, or anaphthyl group,

xe21 may be an integer from 1 to 5.

In one embodiment, at least one of Ar₆₀₁(s) in the number of xe11 andR₆₀₁(s) in the number of xe21 may include the π electron-depletednitrogen-containing ring.

In one embodiment, ring Ar₆₀₁ in Formula 601 may be selected from:

a benzene group, a naphthalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, a dibenzofuran group, adibenzothiophene group, a carbazole group, an imidazole group, apyrazole group, a thiazole group, an isothiazole group, an oxazolegroup, an isoxazole group, a pyridine group, a pyrazine group, apyrimidine group, a pyridazine group, an indazole group, a purine group,a quinoline group, an isoquinoline group, a benzoquinoline group, aphthalazine group, a naphthyridine group, a quinoxaline group, aquinazoline group, a cinnoline group, a phenanthridine group, anacridine group, a phenanthroline group, a phenazine group, abenzimidazole group, an iso-benzothiazole group, a benzoxazole group, anisobenzoxazole group, a triazole group, a tetrazole group, an oxadiazolegroup, a triazine group, a thiadiazole group, an imidazopyridine group,an imidazopyrimidine group, and an azacarbazole group;

a benzene group, a naphthalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, a dibenzofuran group, adibenzothiophene group, a carbazole group, an imidazole group, apyrazole group, a thiazole group, an isothiazole group, an oxazolegroup, an isoxazole group, a pyridine group, a pyrazine group, apyrimidine group, a pyridazine group, an indazole group, a purine group,a quinoline group, an isoquinoline group, a benzoquinoline group, aphthalazine group, a naphthyridine group, a quinoxaline group, aquinazoline group, a cinnoline group, a phenanthridine group, anacridine group, a phenanthroline group, a phenazine group, abenzimidazole group, an iso-benzothiazole group, a benzoxazole group, anisobenzoxazole group, a triazole group, a tetrazole group, an oxadiazolegroup, a triazine group, a thiadiazole group, an imidazopyridine group,an imidazopyrimidine group, and an azacarbazole group, each substitutedwith at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, aphenyl group, a biphenyl group, a terphenyl group, a naphthyl group,—Si(Q₃₁)(Q₃₂)(Q₃₃), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂); and

Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

When xe11 in Formula 601 is two or more, two or more Ar₆₀₁(s) may belinked via a single bond.

In one or more embodiments, Ar₆₀₁ in Formula 601 may be an anthracenegroup.

In one or more embodiments, a compound represented by Formula 601 may berepresented by Formula 601-1:

In Formula 601-1,

X₆₁₄ may be N or C(R₆₁₄), X₆₁₅ may be N or C(R₆₁₅), X₆₁₆ may be N orC(R₆₁₆), and at least one selected from X₆₁₄ to X₆₁₆ may be N,

L₆₁₁ to L₆₁₃ may each independently be the same as described inconnection with L₆₀₁,

xe611 to xe613 may each independently be the same as described inconnection with xe1,

R₆₁₁ to R₆₁₃ may each independently be the same as described inconnection with R₆₀₁, and

R₆₁₄ to R₆₁₆ may each independently be selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, and a naphthyl group.

In one embodiment, L₆₀₁ and L₆₁₁ to L₆₁₃ in Formulae 601 and 601-1 mayeach independently be selected from:

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, anaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenylgroup, a hexacenyl group, a pentacenyl group, a thiophenyl group, afuranyl group, a carbazolyl group, an indolyl group, an isoindolylgroup, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranylgroup, a dibenzothiophenyl group, a benzocarbazolyl group, adibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, anoxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, abenzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinylgroup, and an azacarbazolyl group;

but embodiments of the present disclosure are not limited thereto.

In one or more embodiments, xe1 and xe611 to xe613 in Formulae 601 and601-1 may each independently be 0, 1, or 2.

In one or more embodiments, R₆₀₁ and R₆₁₁ to R₆₁₃ in Formula 601 and601-1 may each independently be selected from:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group;

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenanthrenyl group, an anthracenyl group, a fluoranthenylgroup, a triphenylenyl group, a pyrenyl group, a chrysenyl group, aperylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a thiophenyl group, a furanyl group, a carbazolyl group, anindolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group;

—S(═O)₂(Q₆₀₁) and —P(═O)(Q₆₀₁)(Q₆₀₂); and

Q₆₀₁ and Q₆₀₂ may be the same as described above.

The electron transport region may include at least one compound selectedfrom Compounds ET1 to ET36, but embodiments of the present disclosureare not limited thereto:

In one or more embodiments, the electron transport region may include atleast one selected from 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline(BCP), 4,7-diphenyl-1,10-phenanthroline (Bphen), Alq3, BAlq,3-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-4-phenyl-4H-1,2,4-triazole(TAZ), and NTAZ.

A thickness of the buffer layer, the hole blocking layer, or theelectron control layer may be in a range of about 20 Å to about 1,000 Å,for example, about 30 Å to about 300 Å. When the thicknesses of thebuffer layer, the hole blocking layer, and the electron control layerare within these ranges, the electron blocking layer may have excellentelectron blocking characteristics or electron control characteristicswithout a substantial increase in driving voltage.

A thickness of the electron transport layer may be in a range of about100 Å to about 1,000 Å, for example, about 150 Å to about 500 Å. Whenthe thickness of the electron transport layer is within the rangedescribed above, the electron transport layer may have suitable orsatisfactory electron transport characteristics without a substantialincrease in driving voltage.

The electron transport region (for example, the electron transport layerin the electron transport region) may further include, in addition tothe materials described above, a metal-containing material.

The metal-containing material may include at least one selected fromalkali metal complex and alkaline earth-metal complex. The alkali metalcomplex may include a metal ion selected from a Li ion, a Na ion, a Kion, a Rb ion, and a Cs ion, and the alkaline earth-metal complex mayinclude a metal ion selected from a Be ion, a Mg ion, a Ca ion, a Srion, and a Ba ion. A ligand coordinated with the metal ion of the alkalimetal complex or the alkaline earth-metal complex may be selected from ahydroxy quinoline, a hydroxy isoquinoline, a hydroxy benzoquinoline, ahydroxy acridine, a hydroxy phenanthridine, a hydroxy phenylan oxazole,a hydroxy phenylthiazole, a hydroxy diphenylan oxadiazole, a hydroxydiphenylthiadiazole, a hydroxy phenylpyridine, a hydroxyphenylbenzimidazole, a hydroxy phenylbenzothiazole, a bipyridine, aphenanthroline, and a cyclopentadiene, but embodiments of the presentdisclosure are not limited thereto.

For example, the metal-containing material may include a Li complex. TheLi complex may include, for example, Compound ET-D1 (lithium quinolate,LiQ) or ET-D2.

The electron transport region may include an electron injection layerthat facilitates the injection of electrons from the second electrode190. The electron injection layer may directly contact the secondelectrode 190.

The electron injection layer may have i) a single-layered structureincluding a single layer including a single material, ii) asingle-layered structure including a single layer including a pluralityof different materials, or iii) a multi-layered structure having aplurality of layers including a plurality of different materials.

The electron injection layer may include an alkali metal, an alkalineearth metal, a rare earth metal, an alkali metal compound, an alkalineearth-metal compound, a rare earth metal compound, an alkali metalcomplex, an alkaline earth-metal complex, a rare earth metal complex, orany combinations thereof.

The alkali metal may be selected from Li, Na, K, Rb, and Cs. In oneembodiment, the alkali metal may be Li, Na, or Cs. In one or moreembodiments, the alkali metal may be Li or Cs, but embodiments of thepresent disclosure are not limited thereto.

The alkaline earth metal may be selected from Mg, Ca, Sr, and Ba.

The rare earth metal may be selected from Sc, Y, Ce, Tb, Yb, and Gd.

The alkali metal compound, the alkaline earth-metal compound, and therare earth metal compound may be selected from oxides and halides (forexample, fluorides, chlorides, bromides, or iodides) of the alkalimetal, the alkaline earth-metal, and the rare earth metal.

The alkali metal compound may be selected from alkali metal oxides, suchas Li₂O, Cs₂O, or K₂O, and alkali metal halides, such as LiF, NaF, CsF,KF, LiI, Nal, CsI, KI, or Rbl. In one embodiment, the alkali metalcompound may be selected from LiF, Li₂O, NaF, LiI, Nal, CsI, and KI, butembodiments of the present disclosure are not limited thereto.

The alkaline earth-metal compound may be selected from alkalineearth-metal oxides, such as BaO, SrO, CaO, Ba_(x)Sr_(1-x)P (0<x<1),Ba_(x)Ca_(1-x)O (0<x<1). In one embodiment, the alkaline earth-metalcompound may be selected from BaO, SrO, and CaO, but embodiments of thepresent disclosure are not limited thereto.

The rare earth metal compound may be selected from YbF₃, ScF₃, ScO₃,Y₂O₃, Ce₂O₃, GdF₃, and TbF₃. In one embodiment, the rare earth metalcompound may be selected from YbF₃, ScF₃, TbF₃, Ybl₃, ScI₃, and Tbl₃,but embodiments of the present disclosure are not limited thereto.

The alkali metal complex, the alkaline earth-metal complex, and the rareearth metal complex may include an ion of alkali metal, alkalineearth-metal, and rare earth metal as described above, and a ligandcoordinated with a metal ion of the alkali metal complex, the alkalineearth-metal complex, or the rare earth metal complex may be selectedfrom hydroxy quinoline, hydroxy isoquinoline, hydroxy benzoquinoline,hydroxy acridine, hydroxy phenanthridine, hydroxy phenylan oxazole,hydroxy phenylthiazole, hydroxy diphenylan oxadiazole, hydroxydiphenylthiadiazole, hydroxy phenylpyridine, hydroxyphenylbenzimidazole, hydroxy phenylbenzothiazole, bipyridine,phenanthroline, and cyclopentadiene, but embodiments of the presentdisclosure are not limited thereto.

The electron injection layer may consist of an alkali metal, an alkalineearth metal, a rare earth metal, an alkali metal compound, an alkalineearth-metal compound, a rare earth metal compound, an alkali metalcomplex, an alkaline earth-metal complex, a rare earth metal complex, orany combinations thereof, as described above. In one or moreembodiments, the electron injection layer may further include an organicmaterial. When the electron injection layer further includes an organicmaterial, an alkali metal, an alkaline earth metal, a rare earth metal,an alkali metal compound, an alkaline earth-metal compound, a rare earthmetal compound, an alkali metal complex, an alkaline earth-metalcomplex, a rare earth metal complex, or any combinations thereof may behomogeneously or non-homogeneously dispersed in a matrix including theorganic material.

A thickness of the electron injection layer may be in a range of about 1Å to about 100 Å, for example, about 3 Å to about 90 Å. When thethickness of the electron injection layer is within the range describedabove, the electron injection layer may have suitable or satisfactoryelectron injection characteristics without a substantial increase indriving voltage.

The second electrode 190 may be disposed on the organic layer 150 havingsuch a structure. The second electrode 190 may be a cathode which is anelectron injection electrode, and in this regard, a material for formingthe second electrode 190 may be selected from metal, an alloy, anelectrically conductive compound, and a combination thereof, which havea relatively low work function.

The second electrode 190 may include at least one selected from lithium(Li), silver (Si), magnesium (Mg), aluminum (Al), aluminum-lithium(Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver(Mg—Ag), ITO, and IZO, but embodiments of the present disclosure are notlimited thereto. The second electrode 190 may be a transmissiveelectrode, a semi-transmissive electrode, or a reflective electrode.

The second electrode 190 may have a single-layered structure, or amulti-layered structure including two or more layers.

Hereinbefore, the organic light-emitting device has been described withreference to the accompanying drawing, but embodiments of the presentdisclosure are not limited thereto.

Layers constituting the hole transport region, an emission layer, andlayers constituting the electron transport region may be formed in acertain region by using one or more suitable methods selected fromvacuum deposition, spin coating, casting, Langmuir-Blodgett (LB)deposition, ink-jet printing, laser-printing, and laser-induced thermalimaging.

When layers constituting the hole transport region, an emission layer,and layers constituting the electron transport region are formed byvacuum deposition, for example, the vacuum deposition may be performedat a deposition temperature of about 100° C. to about 500° C., at avacuum degree of about 10⁻⁸ torr to about 10⁻³ torr, and at a depositionrate of about 0.01 Å/sec to about 100 Å/sec by taking into account amaterial to be included in a layer to be formed, and the structure of alayer to be formed.

When layers constituting the hole transport region, an emission layer,and layers constituting the electron transport region are formed by spincoating, the spin coating may be performed at a coating speed of about2,000 rpm to about 5,000 rpm and at a heat treatment temperature ofabout 80° C. to about 200° C. by taking into account a material to beincluded in a layer to be formed, and the structure of a layer to beformed.

The term “C₁-C₆₀ alkyl group,” as used herein, refers to a linear orbranched saturated aliphatic hydrocarbon monovalent group having 1 to 60carbon atoms, and non-limiting examples thereof include a methyl group,an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, atert-butyl group, a pentyl group, an iso-amyl group, and a hexyl group.The term “C₁-C₆₀ alkylene group,” as used herein, refers to a divalentgroup having substantially the same structure as the C₁-C₆₀ alkyl group,except that the C₁-C₆₀ alkylene group is divalent instead of monovalent.

The term “C₂-C₆₀ alkenyl group,” as used herein, refers to a hydrocarbongroup formed by substituting at least one carbon-carbon double bond at amain chain (e.g., in the middle) or at the terminus of the C₂-C₆₀ alkylgroup, and non-limiting examples thereof include an ethenyl group, apropenyl group, and a butenyl group. The term “C₂-C₆₀ alkenylene group,”as used herein, refers to a divalent group having substantially the samestructure as the C₂-C₆₀ alkenyl group, except that the C₂-C₆₀ alkenylenegroup is divalent instead of monovalent.

The term “C₂-C₆₀ alkynyl group,” as used herein, refers to a hydrocarbongroup having at least one carbon-carbon triple bond at a main chain(e.g., in the middle) or at the terminus of the C₂-C₆₀ alkyl group, andnon-limiting examples thereof include an ethynyl group, and a propynylgroup. The term “C₂-C₆₀ alkynylene group,” as used herein, refers to adivalent group having substantially the same structure as the C₂-C₆₀alkynyl group, except that the C₂-C₆₀ alkynylene group is divalentinstead of monovalent.

The term “C₁-C₆₀ alkoxy group,” as used herein, refers to a monovalentgroup represented by —OA₁₀₁ (wherein A₁₀₁ is the C₁-C₆₀ alkyl group),and non-limiting examples thereof include a methoxy group, an ethoxygroup, and an isopropyloxy group.

The term “C₃-C₁₀ cycloalkyl group,” as used herein, refers to amonovalent saturated hydrocarbon monocyclic group having 3 to 10 carbonatoms, and non-limiting examples thereof include a cyclopropyl group, acyclobutyl group, a cyclopentyl group, a cyclohexyl group, and acycloheptyl group. The term “C₃-C₁₀ cycloalkylene group,” as usedherein, refers to a divalent group having substantially the samestructure as the C₃-C₁₀ cycloalkyl group, except that the C₃-C₁₀cycloalkylene group is divalent instead of monovalent.

The term “C₁-C₁₀ heterocycloalkyl group,” as used herein, refers to amonovalent monocyclic group having at least one heteroatom selected fromN, O, Si, P, and S as a ring-forming atom and 1 to 10 carbon atoms, andnon-limiting examples thereof include a 1,2,3,4-oxatriazolidinyl group,a tetrahydrofuranyl group, and a tetrahydrothiophenyl group. The term“C₁-C₁₀ heterocycloalkylene group,” as used herein, refers to a divalentgroup having substantially the same structure as the C₁-C₁₀heterocycloalkyl group, except that the C₁-C₁₀ heterocycloalkylene groupis divalent instead of monovalent.

The term “C₃-C₁₀ cycloalkenyl group,” as used herein, refers to amonovalent monocyclic group that has 3 to 10 carbon atoms and at leastone carbon-carbon double bond in the ring thereof and no aromaticity(e.g., the ring or the entire group is not aromatic), and non-limitingexamples thereof include a cyclopentenyl group, a cyclohexenyl group,and a cycloheptenyl group. The term “C₃-C₁₀ cycloalkenylene group,” asused herein, refers to a divalent group having substantially the samestructure as the C₃-C₁₀ cycloalkenyl group, except that the C₃-C₁₀cycloalkenylene group is divalent instead of monovalent.

The term “C₁-C₁₀ heterocycloalkenyl group,” as used herein, refers to amonovalent monocyclic group that has at least one heteroatom selectedfrom N, O, Si, P, and S as a ring-forming atom, 1 to 10 carbon atoms,and at least one carbon-carbon double bond in its ring. Non-limitingexamples of the C₁-C₁₀ heterocycloalkenyl group include a4,5-dihydro-1,2,3,4-oxatriazolyl group, a 2,3-dihydrofuranyl group, anda 2,3-dihydrothiophenyl group. The term “C₁-C₁₀ heterocycloalkenylenegroup,” as used herein, refers to a divalent group having substantiallythe same structure as the C₁-C₁₀ heterocycloalkenyl group, except thatthe C₁-C₁₀ heterocycloalkenylene group is divalent instead ofmonovalent.

The term “C₆-C₆₀ aryl group,” as used herein, refers to a monovalentgroup having a carbocyclic aromatic system having 6 to 60 carbon atoms,and the term “C₆-C₆₀ arylene group,” as used herein, refers to adivalent group having a carbocyclic aromatic system having 6 to 60carbon atoms. Non-limiting examples of the C₆-C₆₀ aryl group include aphenyl group, a naphthyl group, an anthracenyl group, a phenanthrenylgroup, a pyrenyl group, and a chrysenyl group. When the C₆-C₆₀ arylgroup and the C₆-C₆₀ arylene group each include two or more rings, therings may be fused to each other.

The term “C₁-C₆₀ heteroaryl group,” as used herein, refers to amonovalent group having a heterocyclic aromatic system that has at leastone heteroatom selected from N, O, Si, P, and S as a ring-forming atom,in addition to 1 to 60 carbon atoms. The term “C₁-C₆₀ heteroarylenegroup,” as used herein, refers to a divalent group having a heterocyclicaromatic system that has at least one heteroatom selected from N, O, Si,P, and S as a ring-forming atom, in addition to 1 to 60 carbon atoms.Non-limiting examples of the C₁-C₆₀ heteroaryl group include a pyridinylgroup, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, atriazinyl group, a quinolinyl group, and an isoquinolinyl group. Whenthe C₁-C₆₀ heteroaryl group and the C₁-C₆₀ heteroarylene group eachinclude two or more rings, the rings may be fused to each other (e.g.,the rings may be combined together).

The term “C₆-C₆₀ aryloxy group,” as used herein, indicates —OA₁₀₂(wherein A₁₀₂ is the C₆-C₆₀ aryl group), and the term “C₆-C₆₀ arylthiogroup,” as used herein, indicates —SA₁₀₃ (wherein A₁₀₃ is the C₆-C₆₀aryl group).

The term “monovalent non-aromatic condensed polycyclic group,” as usedherein, refers to a monovalent group (for example, having 8 to 60 carbonatoms) having two or more rings condensed with each other (e.g., two ormore rings combined or fused together), only carbon atoms asring-forming atoms, and no aromaticity in its entire molecular structure(e.g., the entire molecular structure is non-aromatic). A detailed,non-limiting, example of the monovalent non-aromatic condensedpolycyclic group is a fluorenyl group. The term “divalent non-aromaticcondensed polycyclic group,” as used herein, refers to a divalent grouphaving substantially the same structure as the monovalent non-aromaticcondensed polycyclic group, except that the divalent non-aromaticcondensed polycyclic group is divalent instead of monovalent.

The term “monovalent non-aromatic condensed heteropolycyclic group,” asused herein, refers to a monovalent group (for example, having 1 to 60carbon atoms) having two or more rings condensed to each other (e.g.,two or more rings combined or fused together), at least one heteroatomselected from N, O, Si, P, and S, other than carbon atoms, as aring-forming atom, and no aromaticity in its entire molecular structure(e.g., the entire molecular structure is non-aromatic). A non-limitingexample of the monovalent non-aromatic condensed heteropolycyclic groupis a carbazolyl group. The term “divalent non-aromatic condensedheteropolycyclic group,” as used herein, refers to a divalent grouphaving substantially the same structure as the monovalent non-aromaticcondensed heteropolycyclic group, except that the divalent non-aromaticcondensed heteropolycyclic group is divalent instead of monovalent.

The term “C₅-C₆₀ carbocyclic group,” as used herein, refers to amonocyclic or polycyclic group having 5 to 60 carbon atoms in which aring-forming atom is a carbon atom only. The C₅-C₆₀ carbocyclic groupmay be an aromatic carbocyclic group or a non-aromatic carbocyclicgroup. The C₅-C₆₀ carbocyclic group may be a ring, such as a benzenegroup, a monovalent group, such as a phenyl group, or a divalent group,such as a phenylene group. In one or more embodiments, depending on thenumber of substituents connected to the C₅-C₆₀ carbocyclic group, theC₅-C₆₀ carbocyclic group may be a trivalent group or a quadrivalentgroup.

The term “C₁-C₆₀ heterocyclic group,” as used herein, refers to a grouphaving the same structure as the C₁-C₆₀ carbocyclic group, except thatas a ring-forming atom, at least one heteroatom selected from N, O, Si,P, and S is used in addition to carbon (the number of carbon atoms maybe in a range of 1 to 60).

At least one substituent of the substituted C₅-C₆₀ carbocyclic group,the substituted C₁-C₆₀ heterocyclic group, the substituted C₃-C₁₀cycloalkylene group, the substituted C₁-C₁₀ heterocycloalkylene group,the substituted C₃-C₁₀ cycloalkenylene group, the substituted C₁-C₁₀heterocycloalkenylene group, the substituted C₆-C₆₀ arylene group, thesubstituted C₁-C₆₀ heteroarylene group, the substituted divalentnon-aromatic condensed polycyclic group, the substituted divalentnon-aromatic condensed heteropolycyclic group, the substituted C₁-C₆₀alkyl group, the substituted C₂-C₆₀ alkenyl group, the substitutedC₂-C₆₀ alkynyl group, the substituted C₁-C₆₀ alkoxy group, thesubstituted C₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenyl group, thesubstituted C₁-C₁₀ heterocycloalkenyl group, the substituted C₆-C₆₀ arylgroup, the substituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀arylthio group, the substituted C₁-C₆₀ heteroaryl group, the substitutedmonovalent non-aromatic condensed polycyclic group, and the substitutedmonovalent non-aromatic condensed heteropolycyclic group may be selectedfrom:

deuterium (—D), —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, anda C₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amidino group, a hydrazino group, a hydrazono group, aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂), —B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁),—S(═O)₂(Q₁₁), and —P(═O)(Q₁₁)(Q₁₂);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, —Si(Q₂₁)(Q₂₂)(Q₂₃),—N(Q₂₁)(Q₂₂), —B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁), —S(═O)₂(Q₂₁), and—P(═O)(Q₂₁)(Q₂₂); and

—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂),

wherein Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ may each independently beselected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, aC₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₁-C₆₀ heteroarylgroup, a monovalent non-aromatic condensed polycyclic group, amonovalent non-aromatic condensed heteropolycyclic group, a biphenylgroup, and a terphenyl group.

The term “Ph,” as used herein, may refer to a phenyl group; the term“Me,” as used herein, may refer to a methyl group; the term “Et,” asused herein, may refer to an ethyl group; the terms “ter-Bu” or “But,”as used herein, may refer to a tert-butyl group; and the term “OMe,” asused herein, may refer to a methoxy group.

The term “biphenyl group,” as used herein, refers to “a phenyl groupsubstituted with a phenyl group.” In other words, the “biphenyl group”is a substituted phenyl group having a C₆-C₆₀ aryl group as asubstituent.

The “terphenyl group,” as used herein, refers to “a phenyl groupsubstituted with a biphenyl group.” In other words, the “terphenylgroup” is a phenyl group having, as a substituent, a C₆-C₆₀ aryl groupsubstituted with a C₆-C₆₀ aryl group.

* and *′, as used herein, unless defined otherwise, each refer to abinding site to a neighboring atom in a corresponding formula.

Hereinafter, a compound according to embodiments and an organiclight-emitting device according to embodiments will be described in moredetail with reference to Synthesis Examples and Examples. The expression“B was used instead of A” used in describing Synthesis Examples andExamples means that an identical or substantially identical number ofmolar equivalents of A was used in place of molar equivalents of B.

SYNTHESIS EXAMPLE Synthesis of Compound 1 1) Synthesis ofbis(2-bromophenylamine)

15 g (0.087 mol) of 2-bromoaniline and 29.6 g (0.105 mol) of1-bromo-2-iodobenzene were dissolved in 200 mL of toluene in a 500-mLthree-neck round bottom flask, and 16.76 g (0.174 mol) of sodiumtert-butoxide, 12.76 g (0.017 mol) of Pd(dppf)Cl₂, and 7.98 g (0.009mol) of Pd₂dba₃ were added thereto. The mixture was stirred under refluxfor 12 hours. When the reaction was substantially completed, the solventwas removed from the mixture, and an extraction process was performedthereon three times by using methylene chloride (MC). An extractedorganic layer was dried by using MgSO₄ and the solvent was removedtherefrom by using a rotary evaporator. The residue obtained therefromwas separated using an n-hexane solvent by column chromatography toobtain 18.3 g (yield=64%) of a colorless oil-like compound.

¹H-NMR (300 MHz, CDCl₃) [ppm] δ=7.64-7.61 (d, 2H), 7.35-7.32 (d, 2H),7.28-7.22 (t, 2H), 6.91-6.85 (t, 2H), 6.50 (s, 1H).

2) Synthesis of N,N-bis(2-bromophenyl)-N-(4-methoxybenzyl)amine

39 g (119.2 mmol) of bis(2-bromophenylamine), 3.43 g (143.1 mol) of NaH,and 250 mL of dimethylformamide (DMF) were added to a well-dried 500-mLthree-neck round bottom flask in an nitrogen atmosphere and stirred atroom temperature (25° C.) for 1 hour. Then, 20.54 g (131.2 mol) of1-(chloromethyl)-4-methoxybenzene was added thereto dropwise and stirredat room temperature for 14 hours. After the reaction was substantiallycompleted, 500 mL of distilled water was added to the reaction mixturedropwise to filter and separate a precipitated solid. The filtered solidwas redissolved in MC and an extraction process was performed thereonthree times. An extracted organic layer was dried by using MgSO₄ and thesolvent was evaporated by using a rotary evaporator. The residueobtained therefrom was separated using a solvent (MC:hexane=3:1) bycolumn chromatography to obtain 46.8 g (yield=87%) of a compound.

¹H-NMR (300 MHz, DMSO) [ppm] δ=7.64-7.61 (d, 2H), 7.5 (d, 2H), 7.3 (t,2H), 7.0 (m, 4H), 6.80 (d, 2H), 4.7 (s, 2H), 3.7 (s, 3H).

3) Synthesis of 5-(4-methoxybenzyl)-10-phenyl-5H-phenophosphazine10-oxide

7.00 g (15.6 mmol) of2-bromo-N-(2-bromophenyl)-N-(4-methoxybenzyl)aniline and 100 mL of etherwere added to a 150-mL three-neck round bottom flask and then stirred. Areaction temperature was lowered to a temperature of −5° C., and 13.8 mL(34.4 mmol) of 2.5M n-BuLi/Hex was added thereto dropwise. After theresultant mixture was stirred for 40 minutes while maintaining thereaction temperature, the reaction temperature was lowered to atemperature of −78° C. and 2.5 mL (18.8 mmol) of dichlorophenylphosphinedissolved in 20 mL of ether was added thereto dropwise. Then, theresultant mixture was stirred at room temperature for 12 hours. Afterthe reaction was substantially completed, the solvent was removedtherefrom, and an extraction process was performed thereon three timesby using ethyl acetate. An extracted organic layer was dried by usingMgSO₄, and the solvent was removed therefrom by using a rotaryevaporator. 70 mL of methylene dichloride and 30 mL of H₂O₂ were addedthereto and stirred at room temperature for 12 hours. An extractionprocess was performed thereon three times by using methylene dichloride.Then, an extracted organic layer was dried by using MgSO₄, and thesolvent was evaporated by using a rotary evaporator. The residueobtained therefrom was separated using a solvent (ethylacetate:hexane=5:1) by column chromatography to obtain 4 g (yield=52%)of a compound.

¹H-NMR (300 MHz, DMSO) [ppm] δ=7.85-7.77 (dd, 2H), 7.65-7.58 (dd, 2H),7.52-7.42 (m, 5H), 7.19-7.13 (m, 6H), 6.96-6.92 (d, 2H), 5.37 (s, 2H),3.83 (s, 3H).

4) Synthesis of 10-phenyl-5H-phenophosphazine 10-oxide

29.17 g (218.7 mmol) of AlCl₃ and 200 mL of anisole were added to a100-mL three-neck round bottom flask. A reaction temperature was loweredto −5° C. and 12 g (29.1 mmol) of5-(4-methoxybenzyl)-10-phenyl-5H-phenophosphazinine 10-oxide wasdissolved in 100 mL of anisole and stirred at a temperature of 70° C.for 14 hours. After the reaction was substantially completed, H₂O wasadded thereto and an extraction process was performed thereon threetimes by using a toluene solvent. An extracted organic layer was driedby using MgSO₄, and the solvent was removed therefrom by using a rotaryevaporator. The residue obtained therefrom was separated using an ethylacetate/methanol (9:1) solvent by column chromatography to obtain 5.6 g(yield=66%) of a compound.

5) Synthesis of Compound 1

3.2 g (8.24 mmol) of 2-(4-bromophenyl)-4,6-diphenyl-1,3,5-triazine, 2 g(6.87 mmol) of 10-phenyl-5H-phenophosphazinine 10-oxide, 1.98 g (20.60mmol) of sodium-tert-butoxide, 0.14 g (0.69 mmol) oftris(tert-butyl)phosphine, and 0.31 g (0.34 mmol) of Pd₂(dba)₃ weredissolved in 50 mL of toluene and stirred at a temperature of 110° C.for 12 hours in a 30-mL three-neck round bottom flask. After thereaction was substantially completed, water was added thereto, and anextraction process was performed thereon three times by usingchloroform. An extracted organic layer was dried by using MgSO₄, and thesolvent was removed therefrom by using a rotary evaporator. The residueobtained therefrom was separated using an ethyl acetate solvent bycolumn chromatography to obtain 0.54 g (yield=63%) of Compound 1.

¹H-NMR (300 MHz, CD₂Cl₂) [ppm] δ=9.18-9.14 (d, 2H), 8.90-8.86 (d, 4H),7.85-7.64 (m, 12H), 7.54-7.50 (m, 3H), 7.41-7.36 (t, 2H), 7.16-7.11 (t,2H), 6.71-6.67 (t, 2H). Mass: C39H27N4OP calcd. 598.19; found. 598.19.

EXAMPLE Example 1

As an anode, a Corning 15 Ω/cm² (1,000 Å) ITO glass substrate was cut toa size of 50 mm×50 mm×0.5 mm, sonicated with isopropyl alcohol and purewater each for 10 minutes, and then cleaned by exposure to ultravioletrays and ozone for 10 minutes. Then, the resultant ITO glass substratewas provided to a vacuum deposition apparatus.

DNTPD was vacuum-deposited on the ITO glass substrate to form a holeinjection layer having a thickness of 600 Å, and NPB wasvacuum-deposited on the hole injection layer to form a hole transportlayer having a thickness of 600 Å.

CBP was vacuum-deposited on the hole transport layer to form a Bauxiliary layer having a thickness of 100 Å, and Flrpic (bluephosphorescent dopant) and Compound 1 (host) were co-deposited on the Bauxiliary layer to a weight ratio of 300:15 to form a blue emissionlayer having a thickness of 300 Å.

Then, TSPO was vacuum-deposited on the emission layer to form a holeblocking layer having a thickness of 100 Å, and ET1 and LiQ werevacuum-deposited on the hole blocking layer at a ratio of 50:50 to forman electron transport layer having a thickness of 300 Å.

LiQ was vacuum-deposited on the electron transport layer to form anelectron injection layer having a thickness of 20 Å, and Al wasvacuum-deposited on the electron injection layer to form a cathodehaving a thickness of 1,000 Å, thereby completing the manufacture of anorganic light-emitting device.

Example 2

An organic light-emitting device was manufactured in substantially thesame manner as in Example 1, except that Compound 2 was used instead ofCompound 1 in forming an emission layer.

Example 3

An organic light-emitting device was manufactured in substantially thesame manner as in Example 1, except that Compound 3 was used instead ofCompound 1 in forming an emission layer.

Example 4

An organic light-emitting device was manufactured in substantially thesame manner as in Example 1, except that Compound 4 was used instead ofCompound 1 in forming an emission layer.

Comparative Example 1

An organic light-emitting device was manufactured in substantially thesame manner as in Example 1, except that CBP was used instead ofCompound 1 in forming an emission layer.

Comparative Example 2

An organic light-emitting device was manufactured in substantially thesame manner as in Example 1, except that Comparative Compound 1 was usedinstead of Compound 1 in forming an emission layer.

Evaluation Example 1

A driving voltage, emission efficiency, and color coordinates of theorganic light-emitting devices manufactured according to Examples 1 to 4and Comparative Examples 1 and 2 were measured by using a Keithley SMU236 and a luminance meter PR650 at 600 nit. Results thereof are shown inTable 1.

TABLE 1 Driving Emission voltage efficiency Color (V) (cd/A) coordinatesExample 1 5.1 27.4 (0.18, 0.31) (Compound 1) Example 2 5.3 26.8 (0.18,0.30) (Compound 2) Example 3 5.2 25.2 (0.18, 0.32) (Compound 3) Example4 5.9 23.8 (0.17, 0.29) (Compound 4) Comparative 7.8 18.3 (0.18, 0.30)Example 1 (CBP) Comparative 4.8 8.2 (0.18, 0.33) Example 2 (ComparativeCompound 1)

Referring to Table 1, it is confirmed that the driving voltage of eachof the organic light-emitting devices of Examples 1 to 4 is lower thanthe driving voltage of each of the organic light-emitting devices ofComparative Examples 1 and 2. Also, it is confirmed that the emissionefficiency of each of the organic light-emitting devices of Examples 1to 4 is more excellent than the emission efficiency of the organiclight-emitting devices of Comparative Examples 1 and 2.

According to one or more embodiments, an organic light-emitting deviceincluding the heterocyclic compound may have a low driving voltage, highefficiency, high luminance, and a long lifespan.

It should be understood that embodiments described herein should beconsidered in a descriptive sense only and not for purposes oflimitation. Descriptions of features or aspects within each embodimentshould typically be considered as available for other similar featuresor aspects in other embodiments.

It will be understood that, although the terms “first,” “second,”“third,” etc., may be used herein to describe various elements,components, regions, layers and/or sections, these elements, components,regions, layers and/or sections should not be limited by these terms.These terms are used to distinguish one element, component, region,layer or section from another element, component, region, layer orsection. Thus, a first element, component, region, layer or sectiondescribed below could be termed a second element, component, region,layer or section, without departing from the spirit and scope of thepresent disclosure.

Spatially relative terms, such as “beneath,” “below,” “lower,” “under,”“above,” “upper,” and the like, may be used herein for ease ofexplanation to describe one element or feature's relationship to anotherelement(s) or feature(s) as illustrated in the figures. It will beunderstood that the spatially relative terms are intended to encompassdifferent orientations of the device in use or in operation, in additionto the orientation depicted in the figures. For example, if the devicein the figures is turned over, elements described as “below” or“beneath” or “under” other elements or features would then be oriented“above” the other elements or features. Thus, the example terms “below”and “under” can encompass both an orientation of above and below. Thedevice may be otherwise oriented (e.g., rotated 90 degrees or at otherorientations) and the spatially relative descriptors used herein shouldbe interpreted accordingly.

It will be understood that when an element or layer is referred to asbeing “on,” “connected to,” or “coupled to” another element or layer, itcan be directly on, connected to, or coupled to the other element orlayer, or one or more intervening elements or layers may be present. Inaddition, it will also be understood that when an element or layer isreferred to as being “between” two elements or layers, it can be theonly element or layer between the two elements or layers, or one or moreintervening elements or layers may also be present.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the presentdisclosure. As used herein, the singular forms “a” and “an” are intendedto include the plural forms as well, unless the context clearlyindicates otherwise. It will be further understood that the terms“comprises,” “comprising,” “includes,” and “including,” when used inthis specification, specify the presence of the stated features,integers, acts, operations, elements, and/or components, but do notpreclude the presence or addition of one or more other features,integers, acts, operations, elements, components, and/or groups thereof.

As used herein, the terms “substantially,” “about,” and similar termsare used as terms of approximation and not as terms of degree, and areintended to account for the inherent deviations in measured orcalculated values that would be recognized by those of ordinary skill inthe art. Further, the use of “may” when describing embodiments of thepresent disclosure refers to “one or more embodiments of the presentdisclosure.” As used herein, the terms “use,” “using,” and “used” may beconsidered synonymous with the terms “utilize,” “utilizing,” and“utilized,” respectively. Also, the term “exemplary” is intended torefer to an example or illustration.

Also, any numerical range recited herein is intended to include allsubranges of the same numerical precision subsumed within the recitedrange. For example, a range of “1.0 to 10.0” is intended to include allsubranges between (and including) the recited minimum value of 1.0 andthe recited maximum value of 10.0, that is, having a minimum value equalto or greater than 1.0 and a maximum value equal to or less than 10.0,such as, for example, 2.4 to 7.6. Any maximum numerical limitationrecited herein is intended to include all lower numerical limitationssubsumed therein, and any minimum numerical limitation recited in thisspecification is intended to include all higher numerical limitationssubsumed therein. Accordingly, Applicant reserves the right to amendthis specification, including the claims, to expressly recite anysub-range subsumed within the ranges expressly recited herein.

While one or more embodiments have been described with reference to theaccompanying drawing, it will be understood by those of ordinary skillin the art that various changes in form and details may be made thereinwithout departing from the spirit and scope as defined by the followingclaims, and equivalents thereof.

What is claimed is:
 1. A heterocyclic compound represented by Formula 1:

wherein, in Formula 1, L₁ and L₂ are each independently a substituted orunsubstituted C₅-C₆₀ carbocyclic group or a substituted or unsubstitutedC₁-C₆₀ heterocyclic group, R₁ and R₃ to R₁₀ are each independentlyselected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, —Si(Q₃₁)(Q₃₂)(Q₃₃), P(═O)(Q₃₁)(Q₃₂), asubstituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group, a biphenyl group, and a terphenyl group, R₂ isselected from groups represented by Formulae W-1 to W-16 and N-8 toN-59:

wherein, in Formulae W-1 to W-16, R_(w) is selected from a cyano group,a C₁-C₂₀ fluoroalkyl group, and groups represented by Formulae N-8 toN-59, and in Formulae W-1 to W-16 and N-8 to N-59, Z₅₁ and Z₅₂ are eachindependently selected from hydrogen, deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀fluoroalkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenylgroup, a terphenyl group, a naphthyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, an imidazolyl group, a pyrazole group, a thiazolyl group,an isothiazolyl group, an oxazolyl group, an isoxazolyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group, a dibenzofuranyl group, adibenzothiophenyl group, a triazinyl group, an indazolyl group, apurinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, acinnolinyl group, a phenanthridinyl group, an acridinyl group, aphenanthrolinyl group, a phenazinyl group, a benzimidazolyl group, anisobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group,a triazolyl group, a tetrazolyl group, an oxadiazolyl group, athiadiazolyl group, an imidazopyridinyl group, an imidazopyrimidinylgroup, and an azacarbazolyl group, g2 is an integer from 0 to 2, g3 isan integer from 0 to 3, g4 is an integer from 0 to 4, g5 is an integerfrom 0 to 5, g6 is an integer from 0 to 6, and * indicates a bindingsite to a neighboring atom, a1 is an integer from 0 to 5, a2 is aninteger from 0 to 5, b1 is an integer from 0 to 5, b2 is an integer from1 to 5, at least one substituent of the substituted C₅-C₆₀ carbocyclicgroup, the substituted C₁-C₆₀ heterocyclic group, the substituted C₁-C₆₀alkyl group, the substituted C₂-C₆₀ alkenyl group, the substitutedC₂-C₆₀ alkynyl group, the substituted C₁-C₆₀ alkoxy group, thesubstituted C₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenyl group, thesubstituted C₁-C₁₀ heterocycloalkenyl group, the substituted C₆-C₆₀ arylgroup, the substituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀arylthio group, the substituted C₁-C₆₀ heteroaryl group, the substitutedmonovalent non-aromatic condensed polycyclic group, the substitutedmonovalent non-aromatic condensed heteropolycyclic group, and thesubstituted π electron-depleted nitrogen-containing ring group isselected from: deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynylgroup, and a C₁-C₆₀ alkoxy group; a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenylgroup, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, and a monovalent non-aromaticcondensed heteropolycyclic group; a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, a biphenyl group, and a terphenylgroup; a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, aC₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group, a biphenylgroup, and a terphenyl group, each substituted with at least oneselected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynylgroup, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, a biphenyl group, and a terphenylgroup; and —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and Q₃₁ to Q₃₃ are eachindependently selected from hydrogen, deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryl group substituted with a C₁-C₆₀ alkyl group, a C₁-C₆₀ heteroarylgroup, a monovalent non-aromatic condensed polycyclic group, amonovalent non-aromatic condensed heteropolycyclic group, a biphenylgroup, and a terphenyl group.
 2. The heterocyclic compound of claim 1,wherein: R₁ and R₃ to R₁₀ are each independently selected from:hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, —Si(Q₃₁)(Q₃₂)(Q₃₃), a methyl group, an ethyl group, apropyl group, an isobutyl group, a sec-butyl group, a ter-butyl group, apentyl group, an iso-amyl group, a hexyl group, a C₁-C₂₀ alkoxy group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclopentenyl group, a cyclohexenyl group, a phenyl group, a naphthylgroup, a fluorenyl group, a spiro-bifluorenyl group, aspiro-fluorene-benzofluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a pyrenyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyridinyl group, a pyrimidyl group, a quinolinylgroup, an isoquinolinyl group, a benzoquinolinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a biphenyl group, and a terphenyl group; and aphenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenylgroup, a spiro-fluorene-benzofluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a pyrenyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyridinyl group, a pyrimidyl group, a quinolinylgroup, an isoquinolinyl group, a benzoquinolinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a biphenyl group, and a terphenyl group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, —Si(Q₃₁)(Q₃₂)(Q₃₃), a methyl group,an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, ater-butyl group, a pentyl group, an iso-amyl group, a hexyl group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclopentenyl group, a cyclohexenyl group, a phenyl group, a naphthylgroup, a fluorenyl group, a spiro-bifluorenyl group, aspiro-fluorene-benzofluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a pyrenyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyridinyl group, a pyrimidyl group, a quinolinylgroup, an isoquinolinyl group, a benzoquinolinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a biphenyl group, and a terphenyl group, andQ₃₁ to Q₃₃ are each independently selected from hydrogen, deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryl group substituted with a C₁-C₆₀ alkyl group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup, a monovalent non-aromatic condensed heteropolycyclic group, abiphenyl group, and a terphenyl group.
 3. The heterocyclic compound ofclaim 1, wherein: R₁ is selected from: hydrogen, deuterium, a phenylgroup, a naphthyl group, a fluorenyl group, a pyrenyl group, aphenalenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyridinyl group, apyrimidyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a naphthyridinyl group, a quinoxalinyl group, aquinazolinyl group, a carbazolyl group, a phenanthridinyl group, anacridinyl group, a phenanthrolinyl group, a phenazinyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abiphenyl group, and a terphenyl group; and a phenyl group, a naphthylgroup, a fluorenyl group, a pyrenyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyridinyl group, a pyrimidyl group, a quinolinylgroup, an isoquinolinyl group, a benzoquinolinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a biphenyl group, and a terphenyl group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, —Si(Q₃₁)(Q₃₂)(Q₃₃), a methyl group,an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, ater-butyl group, a pentyl group, an iso-amyl group, a hexyl group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclopentenyl group, a cyclohexenyl group, a phenyl group, a naphthylgroup, a fluorenyl group, a pyrenyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyridinyl group, a pyrimidyl group, a quinolinylgroup, an isoquinolinyl group, a benzoquinolinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a biphenyl group, and a terphenyl group, andQ₃₁ to Q₃₃ are each independently selected from hydrogen, deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryl group substituted with a C₁-C₆₀ alkyl group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup, a monovalent non-aromatic condensed heteropolycyclic group, abiphenyl group, and a terphenyl group.
 4. The heterocyclic compound ofclaim 1, wherein: R₁ is selected from groups represented by Formulae A-1to A-15:

wherein, in Formulae A-1 to A-15, Z₃₁ and Z₃₂ are each independentlyselected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkenyl group, a C₁-C₂₀alkynyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group,a terphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group, a triazinyl group,—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), Q₃₁ to Q₃₃ are each independentlyselected from a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, a phenylgroup, a phenyl group substituted with a C₁-C₁₀ alkyl group, a biphenylgroup, a terphenyl group, a naphthyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group, e3 is an integerfrom 1 to 3, e4 is an integer from 1 to 4, e5 is an integer from 1 to 5,e6 is an integer from 1 to 6, e7 is an integer from 1 to 7, e9 is aninteger from 1 to 9, and * indicates a binding site to a neighboringatom.
 5. The heterocyclic compound of claim 1, wherein: R₂ is selectedfrom the following structures:

wherein, in the above structures, * indicates a binding site to aneighboring atom.
 6. The heterocyclic compound of claim 1, wherein: R₃to R₁₀ are each independently selected from: hydrogen, deuterium, aphenyl group, a naphthyl group, a fluorenyl group, a pyrenyl group, aphenalenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyridinyl group, apyrimidyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a naphthyridinyl group, a quinoxalinyl group, aquinazolinyl group, a carbazolyl group, a phenanthridinyl group, anacridinyl group, a phenanthrolinyl group, a phenazinyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abiphenyl group, and a terphenyl group; and a phenyl group, a naphthylgroup, a fluorenyl group, a pyrenyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyridinyl group, a pyrimidyl group, a quinolinylgroup, an isoquinolinyl group, a benzoquinolinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a biphenyl group, and a terphenyl group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, —Si(Q₃₁)(Q₃₂)(Q₃₃), a methyl group,an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, ater-butyl group, a pentyl group, an iso-amyl group, a hexyl group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclopentenyl group, a cyclohexenyl group, a phenyl group, a naphthylgroup, a fluorenyl group, a pyrenyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyridinyl group, a pyrimidyl group, a quinolinylgroup, an isoquinolinyl group, a benzoquinolinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a biphenyl group, and a terphenyl group, andQ₃₁ to Q₃₃ are each independently selected from hydrogen, deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryl group substituted with a C₁-C₆₀ alkyl group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup, a monovalent non-aromatic condensed heteropolycyclic group, abiphenyl group, and a terphenyl group.
 7. The heterocyclic compound ofclaim 1, wherein: at least one of R₄ and R₉ is selected from: a phenylgroup, a naphthyl group, a fluorenyl group, a pyrenyl group, aphenalenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyridinyl group, apyrimidyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a naphthyridinyl group, a quinoxalinyl group, aquinazolinyl group, a carbazolyl group, a phenanthridinyl group, anacridinyl group, a phenanthrolinyl group, a phenazinyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abiphenyl group, and a terphenyl group; and a phenyl group, a naphthylgroup, a fluorenyl group, a pyrenyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyridinyl group, a pyrimidyl group, a quinolinylgroup, an isoquinolinyl group, a benzoquinolinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a biphenyl group, and a terphenyl group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, a methyl group, an ethylgroup, a propyl group, an isobutyl group, a sec-butyl group, a ter-butylgroup, a pentyl group, an iso-amyl group, a hexyl group, a cyclopentylgroup, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, acyclohexenyl group, a phenyl group, a naphthyl group, a pyridinyl group,a pyrimidyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a triazinyl group, a biphenylgroup, and a terphenyl group.
 8. The heterocyclic compound of claim 1,wherein: R₄ and R₉ are each independently selected from the followingstructures:

wherein, in the above structures, * indicates a binding site to aneighboring atom.
 9. A heterocyclic compound represented by Formula 1:

wherein, in Formula 1, L₂ is a substituted or unsubstituted C₅-C₆₀carbocyclic group or a substituted or unsubstituted C₁-C₆₀ heterocyclicgroup, R₁ and R₃ to R₁₀ are each independently selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, —Si(Q₃₁)(Q₃₂)(Q₃₃), P(═O)(Q₃₁)(Q₃₂), a substituted orunsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀alkenyl group, a substituted or unsubstituted C₂-C₆₀ alkynyl group, asubstituted or unsubstituted C₁-C₆₀ alkoxy group, a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,a biphenyl group, and a terphenyl group, R₂ is (i) a C₆-C₆₀ aryl groupsubstituted with at least one electron withdrawing group or (ii) asubstituted or unsubstituted π electron-depleted nitrogen-containingring group, wherein the π electron-depleted nitrogen-containing ringgroup is selected from an imidazole, a pyrazole, a thiazole, anisothiazole, an oxazole, an isoxazole, a pyridine, an indazole, apurine, a quinoline, an isoquinoline, a benzoquinoline, a phthalazine, anaphthyridine, a quinoxaline, a quinazoline, a cinnoline, aphenanthridine, an acridine, a phenanthroline, a phenazine, abenzimidazole, an isobenzothiazole, a benzoxazole, an isobenzoxazole, atriazole, a tetrazole, an oxadiazole, a triazine, a thiadiazole, animidazopyridine, an imidazopyrimidine, and an azacarbazole, a1 is aninteger from 0 to 5, a2 is an integer from 0 to 5, b1 is an integer from0 to 5, b2 is an integer from 1 to 5, at least one substituent of thesubstituted C₅-C₆₀ carbocyclic group, the substituted C₁-C₆₀heterocyclic group, the substituted C₁-C₆₀ alkyl group, the substitutedC₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group, thesubstituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀ cycloalkylgroup, the substituted C₁-C₁₀ heterocycloalkyl group, the substitutedC₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenylgroup, the substituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxygroup, the substituted C₆-C₆₀ arylthio group, the substituted C₁-C₆₀heteroaryl group, the substituted monovalent non-aromatic condensedpolycyclic group, the substituted monovalent non-aromatic condensedheteropolycyclic group, and the substituted π electron-depletednitrogen-containing ring group is selected from: deuterium, —F, —Cl,—Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, aC₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group;a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amidino group, a hydrazino group, a hydrazono group, aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group; a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, a biphenyl group, and aterphenyl group; a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkylgroup, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup, a monovalent non-aromatic condensed heteropolycyclic group, abiphenyl group, and a terphenyl group, each substituted with at leastone selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynylgroup, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, a biphenyl group, and a terphenylgroup; and —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and Q₃₁ to Q₃₃ are eachindependently selected from hydrogen, deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryl group substituted with a C₁-C₆₀ alkyl group, a C₁-C₆₀ heteroarylgroup, a monovalent non-aromatic condensed polycyclic group, amonovalent non-aromatic condensed heteropolycyclic group, a biphenylgroup, and a terphenyl group, and L₁ is selected from groups representedby Formulae 3-1 to 3-15:

wherein, in Formulae 3-1 to 3-15, Z₁ is selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid group or a salt thereof, a sulfonic acid groupor a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, achrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group,a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, a dibenzothiophenyl group, a triazinyl group, abenzimidazolyl group, a phenanthrolinyl group, a biphenyl group, and aterphenyl group, d2 is an integer from 0 to 2, d3 is an integer from 0to 3, d4 is an integer from 0 to 4, and * and *′ each indicate a bindingsite to a neighboring atom.
 10. The heterocyclic compound of claim 1,wherein: L₂ is selected from groups represented by Formulae 3-1 to 3-58:

wherein, in Formulae 3-1 to 3-58, Y₁ is O, S, C(Z₃)(Z₄), N(Z₅), orSi(Z₆)(Z₇), Z₁ to Z₇ are each independently selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid group or a salt thereof, a sulfonic acid groupor a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, achrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group,a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, a dibenzothiophenyl group, a triazinyl group, abenzimidazolyl group, a phenanthrolinyl group, a biphenyl group, and aterphenyl group, Z₃ and Z₄ are optionally linked to form a spirostructure, Z₆ and Z₇ are optionally linked to form a spiro structure, d2is an integer from 0 to 2, d3 is an integer from 0 to 3, d4 is aninteger from 0 to 4, d5 is an integer from 0 to 5, d6 is an integer from0 to 6, d8 is an integer from 0 to 8, and * and *′ each indicate abinding site to a neighboring atom.
 11. An organic light-emitting devicecomprising: a first electrode; a second electrode facing the firstelectrode; and an organic layer between the first electrode and thesecond electrode, the organic layer comprising an emission layer and atleast one of the heterocyclic compound of claim
 1. 12. The organiclight-emitting device of claim 11, wherein: the first electrode is ananode, the second electrode is a cathode, the organic layer furthercomprises a hole transport region between the first electrode and theemission layer and an electron transport region between the emissionlayer and the second electrode, the hole transport region comprises atleast one selected from a hole injection layer, a hole transport layer,a buffer layer, an emission auxiliary layer, and an electron blockinglayer, and the electron transport region comprises at least one selectedfrom a hole blocking layer, an electron transport layer, and an electroninjection layer.
 13. The organic light-emitting device of claim 11,wherein: the emission layer comprises the heterocyclic compound.
 14. Theorganic light-emitting device of claim 13, wherein: the emission layerfurther comprises a phosphine oxide-based compound.
 15. The organiclight-emitting device of claim 13, wherein: the hole blocking layercomprises a phosphine oxide-based compound.
 16. The organiclight-emitting device of claim 13, wherein: the hole transport regioncomprises a charge-generation material.
 17. The organic light-emittingdevice of claim 12, wherein: the hole blocking layer comprises theheterocyclic compound.
 18. An organic light-emitting device comprising:an anode; a cathode facing the anode; and an organic layer between theanode and the cathode, the organic layer comprising an emission layerand an electron transport region between the emission layer and theanode, wherein the electron transport region comprises a hole blockinglayer, wherein the electron transport layer comprises a heterocycliccompound represented by Formula 1:

wherein, in Formula 1, L₁ and L₂ are each independently a substituted orunsubstituted C₅-C₆₀ carbocyclic group or a substituted or unsubstitutedC₁-C₆₀ heterocyclic group, R₁ and R₃ to R₁₀ are each independentlyselected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, —Si(Q₃₁)(Q₃₂)(Q₃₃), P(═O)(Q₃₁)(Q₃₂), asubstituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group, a biphenyl group, and a terphenyl group, R₂ is(i) a C₆-C₆₀ aryl group substituted with at least one electronwithdrawing group or (ii) a substituted or unsubstituted πelectron-depleted nitrogen-containing ring group, a1 is an integer from0 to 5, a2 is an integer from 0 to 5, b1 is an integer from 0 to 5, b2is an integer from 1 to 5, at least one substituent of the substitutedC₅-C₆₀ carbocyclic group, the substituted C₁-C₆₀ heterocyclic group, thesubstituted C₁-C₆₀ alkyl group, the substituted C₂-C₆₀ alkenyl group,the substituted C₂-C₆₀ alkynyl group, the substituted C₁-C₆₀ alkoxygroup, the substituted C₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenyl group, thesubstituted C₁-C₁₀ heterocycloalkenyl group, the substituted C₆-C₆₀ arylgroup, the substituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀arylthio group, the substituted C₁-C₆₀ heteroaryl group, the substitutedmonovalent non-aromatic condensed polycyclic group, the substitutedmonovalent non-aromatic condensed heteropolycyclic group, and thesubstituted π electron-depleted nitrogen-containing ring group isselected from: deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynylgroup, and a C₁-C₆₀ alkoxy group; a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenylgroup, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, and a monovalent non-aromaticcondensed heteropolycyclic group; a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, a biphenyl group, and a terphenylgroup; a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, aC₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group, a biphenylgroup, and a terphenyl group, each substituted with at least oneselected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynylgroup, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, a biphenyl group, and a terphenylgroup; and —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and Q₃₁ to Q₃₃ are eachindependently selected from hydrogen, deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryl group substituted with a C₁-C₆₀ alkyl group, a C₁-C₆₀ heteroarylgroup, a monovalent non-aromatic condensed polycyclic group, amonovalent non-aromatic condensed heteropolycyclic group, a biphenylgroup, and a terphenyl group.
 19. A heterocyclic compound selected fromthe following compounds: